There are eight runners in the 100-meter dash. in how many ways can the runners finish first, second, and third?

1. 72
2. 6
3. 120
4. 336

What is the probability of drawing three queens from a standard deck of cards, given that the first card drawn was a queen? assume that the cards are not replaced.

Acylinder has volume 45π and radius 3. what is it’s height?

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.