WAEC Past Questions and Answers - Page 3860

19,296.

Which of the following pH values is the best for the action of the enzymes: renin and pepsin in the
stomach?

A.

pH2

B.

pH7

C.

pH8

D.

pH9

Correct answer is A

No explanation has been provided for this answer.

19,297.

Which of the following food substances is incorrectly linked to its enzyme?

A.

Protein - trypsin

B.

Fat - lipase

C.

Sucrose - pepsin

D.

Starch - amylase

Correct answer is C

No explanation has been provided for this answer.

19,298.

In testing for starch in a leaf, the leaf is first boiled in water for about a minute so that the

A.

cell walls are hardened

B.

cells are killed

C.

chlorophyll is dissolved out

D.

iodine will penetrate

Correct answer is B

No explanation has been provided for this answer.

19,299.

A man suffering from obesity must avoid meals containing

A.

margarine and butter

B.

rice and beans

C.

carrots and oranges

D.

beef and fish

Correct answer is A

No explanation has been provided for this answer.

19,300.

The angle of depression of a point Q from a vertical tower PR, 30m high, is 40°. If the foot P of the tower is on the same horizontal level as Q, find, correct to 2 decimal places, |PQ|.

A.

35.75m

B.

25.00m

C.

22.98m

D.

19.28

Correct answer is A

\(\tan 40° = \frac{30}{|PQ|}\)

\(|PQ| = \frac{30}{\tan 40°} = \frac{30}{0.839}\)

= 35.75m