2015 Necta f4

(For School Candidates Only)

Time: 3 Hours  


1.      This paper consists of sections A, B, C and D.

2.      Answer all questions in sections A, B and C and one (1) question from each part of section D.

3.      Map extract of Kasamwa (sheet 32/4) is provided.

4.      Credit will be given for the use of relevant diagrams.

5.      Calculators and Cellular phones are notallowed in the examination room.

6.      Write your Examination Number on every page of your answer booklet(s)

SECTION A (25 Marks)
Answer all questions in this section.


1. For each of the items (i) ­ (x), choose the correct answer from among the given alternatives and write its letter in theanswer booklet provided.

(i) Autumn, winter, spring and summer are the result of

          A. monsoon

          B. lunar eclipse

          C. rotation

          D. revolution

          E. tides

(ii) A large part of the Southern Hemisphere is covered by

          A. land mass

          B. volcanoes

          C. water mass 
          D. dark clouds
          E. ice.

(iii) The shallow part of the sea that stretches out from the coast is called

          A. Continental shelf           

          B. Continental slope

          C. Ocean ridge

          D. Ocean trench                 

          E. Island.

(iv) Which of the following is not a factor influencing temperature of a place?

          A. Aspect.      

          B. Ocean current.   

          C. Altitude

          D. Eclipse.     

          E. Length of a day.

(v) The sideways erosion which widens the V­shaped valley is known as

          A. vertical erosion    

          B. lateral erosion 

          C. headward erosion 

          D.  hydraulic action

          E. attrition  

(vi)  Deposition of soil materials removed from one horizon to another is called

          A. illuviation

          B. weathering

          C. eluviation      

          D. organic sorting     

          E.  leaching.

(vii) Which of the following results to vertical movements within the earth’s crust?  

          A. Earthquake, faulting and volcanic eruptions.

          B. Block mountains, raised beaches and broad basins.

          C. Volcanic eruptions, rock fall and asymmetric folds.

          D. Fold mountains,basins and asymmetrical folds.

          E. Emerged coasts, over folds and faulting.

(viii) Which among the following features is the impact of water action in the desert?

          A. Yardang

          B. Gullies

          C. Badlands

          D. Sinkhole 

          E. Rock pedestals.

(ix) An active state of decomposition caused by soil microorganism is called

          A. organic matter

          B. soil water

          C. mineral matter

          D. soil air

          E. soil components.

(x) Which of the following is associated with magnitude of an earthquake?
          A. Richter scale

          B. Seismography

          C. Focus  

          D. Epicenter

          E. Tsunami.

2. Match the items in ​List A​ with the responses in ​List B​ by writing the letter of the correct response beside the item number.

(i) Residues that have decomposed and mixed with soil mass.

(ii) Status of soil with respect to amount of elements necessary for plants growth

(iii) Removal of materials from surface of land.

(iv) Vertical section of the soil to the underlying rocks.

(v) Fineness and coarseness of soil particles.
A.Soil type

B.Soil profile

C.Loam soil

D.Soil texture

E.Soil structure

F.Soil fertility

G.Soil organic matters

H.Soil chemistry

I.Soil erosion

J.Soil water

K.Soil Air

3. With the aid of a well labeled diagram, describe the internal structure of the earth.

SECTION B (27 Marks)

Answer all questions this section.


4.Study the following data showing the production of Irish Potatoes in a thousand (“000”) tones in three villages in Tanzania from 2000 to 2002, then answer the questions that follow:
Potato production (“000”)

(a)Construct a compound bar graph to show the production of Irish potatoes in the three villages.

(b)Give three advantages and two disadvantages of the compound bar graph.

(c)Suggest any other methods which could be used to present the data provided in the table.

5.(a)What is an interview?

   (b)Analyze five things to be adhered to for a researcher to have a successful interview.

(6)(a)(i) Define chain survey

           (ii) Give four principle of chain survey

      (b) Give one reason for each of the following

            (i) Ranging pole has a pointed metal end.

            (ii) Note book is important during field study.

            (iii)Back bearings are taken during compass survey.

            (iv) During surveying, measurements are called back by the booker.

SECTION C (28 Marks)

Answer all questions in this section.


7.Study the map extract of Kasamwa (sheet 32/4), then answer the questions that follow:

  (a)Identify two ways that have been used to show relief on the map.

  (b)Draw a relief section to connect Nyabubele Hill at 383834 and Bungwe Hill at 430825.

  (c)Identify the length of the all­weather road in km from grid reference 315844 to 443940.

  (d)Find the bearings of Chabulongo Hill at 367917 to a school at Nyamahuna 349818.

8.Carefully study the photograph given below then answer the questions that follow:

 (a)Name the type of photograph.

 (b)Describe the relief of the area.

 (c)Giving two reasons, describe the scale of production of the crop in the photograph.

 (d)Explain two uses of the crop in the photograph.

 (e)Describe three conditions necessary for the production of the crop.

SECTION D (20 Marks)

Answer one (1) question from each part.


9.Describe six contributions of cash crops production of the economy of United States of America.

10.Analyses six potentials of the Rufiji river basin.


11.Give five reasons for decreasing death rates in many parts of the world.

12.With the aid of examples, describe six factors affecting growth of settlements in Africa.




3.  Description of  the internal structure of the earth and its well labeled diagram.

     The Earth is an oblate spheroid. It is composed of a number of different layers as determined by deep drilling and seismic evidence. These layers are:

   (i)  The core

The core is a layer rich in iron and nickel that is composed of two layers: the inner and outer cores. The   inner core is theorized to be solid with a density of about 13 grams per cubic centimeter and a radius of about 1220 kilometers. The outer core is liquid and has a density of about 11 grams per cubic centimeter. It surrounds the inner core and has an average thickness of about 2250 kilometers.

   (ii) The mantle

The mantle is the mostly-solid bulk of Earth’s interior. The mantle lies between Earth’s dense, super-heated core and its thin outer layer, the crust. The mantle is about 2,900 kilometers (1,802 miles) thick, and makes up a whopping 84% of Earth’s total volume. The mantle is divided into two layers: the upper mantle, and the lower mantle.

   (iii)  The core  

The core is the innermost zone of the internal structure of the earth. - It has diameter of about 69000km (4300 miles) density of about. - The core is also classified into two parts i.e. the outer and inner core. - It separated from the mantle by zone of separation called Gutenberg discontinuity - The outer core is consist of nickel and Iron (NIFE) - It estimated to be 2100 km - The inner core is solid in nature because of high pressure exerted from different parts toward the center - It composed mainly by iron - It has diameter of about 2600 – 2700km. (1600 – 1700 miles).

 Potato production (“000”)


A compound bar graph to show the production of Irish potatoes in the three villages.

(b)  Three advantages of the compound bar graph are

       (i) It is easy to read and interpret as the totals are clearly shown. 

       (ii) It gives a clear visual impression of the total values.

       (iii) It clearly shows the rise and fall in the grand total values.

  Two disadvantages of the compound bar graph are

       (i) The graph is very difficult to construct and interpret.

       (ii) It is not easy to represent a large number of components as this would involve very long bars with many segments.

(c) 0ther methods which could be used to present the data provided in the table are comparative bar graph, divergent bar graph, group line graph, divergent bar graph and compound line graph.

5.(a)  An interview  is the verbal communication/interaction between the interviewer and interviewee, designed to list the information, opinions and feelings they have on their own. It can be through by two ways - Face to face interview or telephone interview.

(b)  Five things to be adhered to for a researcher to have a successful interview are

       (i)  Create friendly atmosphere where two people can talk easily.

       (ii)  Maintain warmth and friendliness. It enables respondent to express in detail their thought and feelings.

       (iii)   Be neutral in note and don’t suggest any answer.

       (iv)   Instill confidence and trust to the respondent by assuming his/her information given would be confidential.

        (v)  Explain briefly the purpose of the interview.

6.(a) (i)  Chain survey is the surveying method in which linear measurements of an area are taken.

         (ii) Four principles of chain survey are

·         Stations should be established first by placing ranging rods (later by pegs if permanent is required) after preliminary reconnaissance survey of the site has been done.

·         Obstacles, steep and uneven slopes should be avoided as far as possible.

·         The triangles should have angles lying between 30° and 120° so as to given clear intersection and check lines must be provided for all independent figures.

·         Field notes should contain a free hand sketch of the area to be surveyed and a neat booking of measured distances.

  (b)  One reason for each of the following are

         (i) Ranging pole has a pointed metal end because it used for marking out key points for measuring.
         (ii) Note book is important during field study because it used for the recording of work done in the field.

         (iii) Back bearings are taken during compass survey because it used to identify the location of an object.
          (iv)  During surveying, measurements are called back by the booker because booker need to record correctly measurements without contain any errors during surveying.

7. (a) Two ways that have been used to show relief on the map are

           (i) Contour and form lines.
           (ii)  Trigonometric Station.


     (c)  To measure the length of the all­weather road in km from grid reference 315844 to 443940 using a sheet of paper.

               By using a piece of paper the map distance of all­weather road is 32.8Cm.

               Scale on map = 1:50000
               Change. 1:50000 into kilometers.

                1km  = 100000cm
                    X   = 50000cm

         100000x = 50000x1

                      x = 50000/100000

                      x =1/2 km (one a half)

    So.        1Cm = 1/2 km
                  32.8= X

                       X=32.8x 1/2
                       X= 16.4 km

  Therefore length of the all­weather road is 16.4 km

    (d) The bearings of Chabulongo Hill at 367917 to a school at Nyamahuna 349818 is 190° SSW

8. (a)  The type of photograph horizontal/ground photograph

    (b)  At the background of the photographs hills and flat landscape are shown.

    (c)   The scale of production of the crop in the photograph is small of production due to the following evidences many crops are grown at once on a photograph and the land cultivated for subsistence farming is always small (less than 5 hectares).

    (d)  Two uses of the crop in the photograph are

           (i) Maize used as Food and

           (ii) Maize used as Medicine.

                   Corn silk (maize long shiny fibers) is used for bladder infections, inflammation of the urinary system, inflammation of the prostate, kidney stones, and bed wetting. It is also used to treat congestive heart failure, diabetes, high blood pressure, fatigue, and high cholesterol levels.

   (e)  Three conditions necessary for the production of the crop are

           (i)  Temperature:

Maize is grown in temperatures between 18°C and 27°C during the day and around 14°C during the night. But the most important factor is the 140 frost-free days. The crop is very susceptible to frost; therefore, its cultivation in temperate latitudes is limited.

            (ii)  Rainfall:

Maize is grown mostly in regions having annual rainfall between 60 mm to 110 mm. But it is also grown in areas having rainfall of about 40 mm.

            (iii)  Soils:

Maize grows in a wide range of soils, ranging from temperate podzols to the leached red soils of the tropics. But, the best suitable soil for maize is deep, rich soils of the sub-tropics, where there is abundant nitrogen.

9. A cash crop is an agricultural crop which is grown for sale to return a profit

    Cash cropping in the United States rose to prominence after the baby boomer generation and the end of World War II. It was seen as a way to feed the large population boom and continues to be the main factor in having an affordable food supply in the United States.

    Six contributions of cash crops production of the economy of United States of America are

       (i)  Availability of land in U.S.A
       (ii) Availability of capital in U.S.A

       (iii) Availability of labour in U.S.A

       (iv)Supply of market

       (v)  Availability of transport and communication network in U.S.A

       (vi)Availability of water supply in U.S.A

10. Rufiji river basin is a river basin found in Tanzania which the government of Tanzania organized the development of Rufiji river basin to support economic activities of the people.

      Six potentials of the Rufiji river basin are

        (i)  It has promoted the market for the Hydro Electric Power (HEP) from Kidatu power plant.

        (ii)  It control floods.

        (iii) The scheme has stimulated the development and maintenance of the railway lines and roads.

        (iv) It has lead to the creation of employment opportunities in the valley.

        (v)  It has promoted living standards of people through employment.

        (vi)  The development of villages and towns, for example new towns like Kidatu,   Makambako and Mikumi.

11. Death rates is the ratio of total deaths to total population in a specified community or area over a specified period of time. The death rate is often expressed as the number of deaths per 1,000 of the population per year. It is also called fatality rate.
       Five reasons for decreasing death rates in many parts of the world are

       (i) Improvement and expansion of health services such as building of new hospitals and expansion of immunization programs.

       (ii)  Family planning programs which have led people to bear few children they can raise.

       (iii)  Improvement of agriculture which has led to increase in food production.

       (iv)  Improvement of transport and communication systems which led to easy distribution of food from areas with surplus to areas with food deficit hence reducing death due to famine.

        (v)  Increase in awareness of importance of personal hygiene.

12. A settlement is a place where people live. A settlement may be as small as a single house in a remote area or as large as a mega city (a city with over 10 million residents), settlement may be permanent or temporary.

      Six factors affecting growth of settlements in Africa are

        (i) Availability of water example places such as Rungwe in Mbeya which has plenty of water have high growth of settlement while areas such as Longido which is arid has low growth rate of settlement

        (ii) Availability of land for agricultural activities For example areas along Kilimanjaro slope which is fertile due to volcanic soil have high growth of settlement compared to areas such as Mpwapwa which is infertile due to soil erosion which low growth rate.

        (iii) Relief of the area

people prefer in areas which are have gentle slopes and tend to avoid settling in areas which have steep slopes due to difficult in establishing infrastructure and thin soil found in the steep slopes. Also people tend to avoid settling in flat areas susceptible to flooding. For example in Katumba Songwe in Kyela people avoid to settle due to floods from river Kiwira.

        (iv) Availability of social services

people prefer to live in areas which have social services such as education, water and electricity and avoid settling in areas which lack social services. For example many rural areas in African continent low settlement growth rate  due lack of social services while urban areas such as Dar es salaam have high settlement growth rate due to abundance of  social service.

        (v) Climatic condition

areas which have adequate rainfall tend to have high growth of settlement due to high agricultural production while areas which experience low rain fall tend to have low growth of settlement due to shortage of water and poor agricultural production.

        (vi) Government policy

government can affect the growth of settlement by forcing people to settle in certain area or persuade people to settle in certain area by supplying social services and other incentives. Also government policy affect settlement growth through town and land use planning. For example there has been a rapid growth of settlement in kinyerezi area on the outskirt of Dar es salaam city due to government decision to allocate that land to settlement and supplying social services.