The triangle ABC above shows the angle of elevation of the top, B, of a tower, BC, from A, to be 30°. AB = 40 m. The length of BC is

Measuring plant growth by measuring height is convenient, but inaccurate because:

Potassium reacts quickly with water but we do not use it with acids because:

In the rectangle above, if ∠AEB = 80°, then ∠DAC =

A liquid compound that conducts electricity is:

Overfishing means:

If x = 2³ × 5² =, then x⁴ =

Which of the following can cross the placenta from mother to fetus?

The biceps and triceps are an antagonistic pair of muscles because:

Which of the following is a prime number?

A detector close to a sample of radioactive material records 76 counts per second (cps). Precisely 2 days later the count rate has fallen to 22 cps.The count rate due to background radiation, taken immediately before and after the experiment, averaged 4 cps. The half-life of the material is:

A cell in an embryo divides by mitosis three times in succession. How many cells will be formed from these divisions?

Difficulty faced at home and the hope of a better life in town BEST illustrate the effect of

Which of the following transactions will NOT affect capital?

Choose the ONE underlined part A, B or C that is inappropriate. If the sentence is acceptable as it stands, choose D.

We could reach the survivors neither by boat or by plane, and so we abandoned our search as futile.

All the following software are examples of operating systems EXCEPT

The method by which certain uranium and plutonium nuclei can release energy in a reactor is known as:

A reaction that gives out heat is said to be:

Which one of the following diagrams illustrates short-sightedness?

(F = Focal point)

Which one of the following statements about ∝ particles is NOT true?