(explain why) a bar magnet is dipolar. this means is has poles.
a. zero
b. one
c. two
d. three

Two poles

Explanation:

The word dipole can be splitted to two; "di" and "pole"; di means 2; hence dipole means 2 poles

A dipolar bar magnet has two poles on the earth surface; these poles are the geomagnetic north pole and the south pole respectively.

In other words, a dipole magnet is a type of magnet in which the opposite poles (which are the North and South poles) are on opposite sides of the magnet.

Away from the surface the dipole becomes distorted. The magnetic field of a bar magnet has a simple configuration known as a dipole field.

the answer for apex is the lowest

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me