WAEC Past Questions and Answers - Page 1744

8,717.

The control of spear grass on the farm is difficult because

A.

It produces a large quantity of seeds

B.

It is easily propagated by suckers

C.

It has a very persistent rhizome

D.

Seeds presist in the soil for a long time

Correct answer is C

No explanation has been provided for this answer.

8,718.

The following salts dissolve readily in cold water except

A.

CaCI2

B.

PbSO4

C.

(NH4)2SO4

D.

Na2CO3

E.

Na2SO3

Correct answer is B

No explanation has been provided for this answer.

8,719.

Copper (ll) tetraoxosulphate (VI) is often added to swimming pools because it

A.

prevents the growth of algae

B.

coagulates suspended particles

C.

neutralizes dissolved gases in water

D.

reacts with any excess chlorine present

E.

increases the amount of dissolved oxygen

Correct answer is A

No explanation has been provided for this answer.

8,720.

Rosette disease of groundnut is transmitted by

A.

An eelworm

B.

A grasshopper

C.

A whitefly

D.

An aphid

Correct answer is D

No explanation has been provided for this answer.