The advantages which firms obtain directly from expanding their operations are referred to as?

• A. internal economies of scale
• B. external economies of scale
• C. economics of localization
• D. economies of resources allocation

The raw scores of 20 students of Utopia High School who took part in an examination in Economics are given below. The pass mark is 40%

38 28 70 43

39 20 64 66

12 46 52 53

20 34 48 69

18 20 64 34

(a) What is the mean score of the students' marks?

(b) How many students passed the examination?

(c) What percentage of the students failed the examination?

(d) What is the range of the scores?

(e) How many students scored below the mean score?

Which of the following husbandry practices is not carried out in pig farming?

• A. castration of excess males
• B. application of iron supplements
• C. numbering by ear notching or tattooing
• D. shearing of hairs of the skin

a)(i) Give two uses of ammonia.

(ii) Name the process by which ammoniacal liquor can be obtained from coal and list two other products of the reaction

(iii) What type of reaction is involved in the conversion of ammoniacal liquor to (NH\(_4\))\(_2\)SO\(_4\) by dilute H\(_2\)SO\(_4\)?

(iv) Sketch and label an energy profile diagram to show the effect of presence of Pt/Rh on the reaction represented by the following equation: 4NH\(_3\) + 5O\(_2\) \(\to\) 6H\(_2\)O + 4NO; \(\Delta\)H = —907 kJmol\(^1\)

(b) Rock salt is an impure form of sodium chloride.

(i) Outline a suitable procedure for preparing a pure sample of sodium chloride from rock salt.

(ii) State two methods that can be used to prepare chlorine from rock salt. Write an appropriate equation in each case.

(c) Lead pigments were used in a water colour painting which turned black after prolonged exposure to an air pollutant. The original colour was restored by using H\(_2\)O\(_2\) which converted the black substance to a simple, white lead (II) salt.

(i) Which pollutant turned the painting black?

(ii) Write the formula of the black substance

(iii) What is the white salt?

(iv) State the role of H\(_2\)O in the restoration process.

Which one of the following changes is physical?

• A) Adding iron filings to aerated water
• B) Adding sodium metal to water
• C) Cooling a solution of iron (II) sulphate to obtain the hydrated salt
• D) Cooling water to obtain ice

This question is based on Thomas Hardy's The Mayor of Casterbirdge.

Hardy employs the character of Henchard to propagate the notion of

• A. confessing our weaknesses
• B. courageously combating adversity
• C. taking steadfast decisions
• D. accepting inevitable defeat

Choose from the options nearest in meaning to the word underlined.

It is time for all concerned to firstpick to pieces the strike action before proffering solutions?

• A. embrace joyfully
• B. critically analyse
• C. stop abruptly
• D. commend highly

A man 1.8m tall stands 3m away from a pin hole camera. If the distance between the pin hole and the screen of the camera is 0.3m. Calculate the height of the image of the man produced by the camera

• A. 0.18m
• B. 0.50m
• C. 1.62m
• D. 18.00m

The basic importance of agriculture to a forester is to

• A. obtain honey
• B. obtain food
• C. acquire labour
• D. procure timber

Good and services are made available to consumers through

• A. the channel of distribution
• B. sales promotion
• C. the advertising agency
• D. the middle men