WAEC Agricultural Science Past Questions & Answers - Page 17

81.

Potassium deficiency in cereal crops is indicated by

A.

Browning of leaves Trom the tips and margins

B.

Yellowing of younger leaves

C.

Purpling of leaves

D.

White and irregular spots on leaves

Correct answer is A

No explanation has been provided for this answer.

82.

Use the information below to answer this question.

In an experiment on soil porosity, the following results were obtained:
Volume of dry soil = 52cm³
Volume of water= 48cm³
Volume of soil and water=78cm³

Calculate the porosity of the soil sample.

A.

28.21%

B.

42.31%

C.

45.83%

D.

61.54%

Correct answer is A

No explanation has been provided for this answer.

83.

Use the information below to answer this question.

In an experiment on soil porosity, the following results were obtained:
Volume of dry soil = 52cm³
Volume of water= 48cm³
Volume of soil and water=78cm³

Determine the volume of airspace in the soil sample.

A.

22cm³

B.

26cm³

C.

30cm³

D.

100cm³

Correct answer is D

No explanation has been provided for this answer.

84.

A difference between physical and chemical weathering is that

A.

There is a change in the mineral composition of rock in physical weathering

B.

The mineral composition of rock is changed in chemical weathering

C.

Carbonation is necessary in physical weathering

D.

Wind is necessary in chemical weathering

Correct answer is B

No explanation has been provided for this answer.

85.

Decomposition of soil organic matter is mainly caused by

A.

Bacteria

B.

Algae

C.

Fungi

D.

Nematodes

Correct answer is A

No explanation has been provided for this answer.