2021 NECO Commerce Past Questions

An object placed 15cm from a converging lens forms a real image whose magnification is 2.0. What is the focal length of the lens?

1. A.5.00cm
2. B.10.00cm✓ Correct
3. C.15.00 cm
4. D.18.00 cm
5. E.20.00cm

Which of these is NOT a basic economic problem of society?

1. A.A. efficiency of resource use✓ Correct
2. B.B. for whom to produces
3. C.C. how to produce
4. D.D. scale of production
5. E.E. what to produce

How many zones are present in a luminous Bunsen burner flame?

1. A.2✓ Correct
2. B.3
3. C.4
4. D.5
5. E.6

What percentage of oxygen is contained in exhaled air?

1. A.21%
2. B.16%
3. C.4%
4. D.0.04%
5. E.Less than 0.01%✓ Correct

The oxidation number of X in $XO_{4}^{3-}$ is

1. A.1
2. B.-2
3. C.3✓ Correct
4. D.4
5. E.5

which of the following properties is/are common to parallelograms and rectangles? I. all angles are right angles II. the diagonals are equals. III. the opposite sides are equal and parallel.

1. A.I and II
2. B.I and III✓ Correct
3. C.II and III
4. D.I
5. E.III

Which metal is extracted from bauxite?

1. A.aluminium
2. B.calcium
3. C.copper✓ Correct
4. D.magnesium
5. E.tin

Choose from the options lettered A - E the one that is most nearly opposite in meaning to the underlined word or expression What belongs to_________belongs to nobody

1. A.anybody
2. B.everybody
3. C.no one
4. D.somebody✓ Correct
5. E.someone

The length, breadth and height of a cuboid are 8cm, 7$\frac{1}{2}$cm and 6$\frac{1}{2}$ cm respectively. What Is its volume in m3 (leave your answer in standard form)?

1. A.3.9 × 10-1m3
2. B.3.9 × 10-2m3✓ Correct
3. C.3.9 × 10-3m3
4. D.3.9 × 10-4m3
5. E.3.9 × 10-5m3

What is the maximum number of electrons that an f-orbital can accommodate?

1. A.2
2. B.6✓ Correct
3. C.7
4. D.10
5. E.14