A loudspeaker emits a steady note.A girl sings a note which is of lower pitch but higher volume. The sound wave she is producing has:

Which of the following BEST characterizes a primary group?

When potassium burns in chlorine, the material that is oxidised is called:

During adolescence, boys:

Compared to industrialised countries, developing countries:

In the figure above, for which point is the x-coordinate positive and the y-coordinate negative?

Which of the relations represented below are functions?

The voltages from the electrochemical series are -2.92 for potassium and +0.34 for copper, which shows that:

The Earth′s first atmosphere contained all of these gases EXCEPT for:

A __________ is a sub-division of a track that stores data on a disk.

The number 2549 written to 2 significant figures is

If p * q = pq² , then 2 * 3 =

A contractor completed five-ninths of a job before a second contractor completed an additional one-third. What fraction of the job is left undone?

A man bought a shirt at a sale. He saves $30 on the normal price when he paid $120 for the shirt. What was the percentage discount on the shirt?

All of the following can affect the size of a population EXCEPT for:

Two separate forces are acting on a bar to cause it to rotate clockwise. One force is 20 N, at a distance of 3 m out from the pivot; the second force, 2 m further out, is 10 N. Their combined moment is:

Which of the following does NOT play a role in evolutionary change?

The range of values of v when 5 - v ≤ 2v - 1 is

Oxidation can include all of these EXCEPT for:

A student observed a plant cell through a microscope and made an accurate drawing of the cell. If her drawing was 80 mm in diameter and had a magnification of ×2000, what was the real diameter of the cell?