I need help with number 5 please!

An arrow is shot vertically upward at a rate of 180ft/s. use the projectile formula h=−16t2+v0t to determine at what time(s), in seconds, the arrow is at a height of 420ft. round your answer(s) to the nearest tenth of a second.

In the diagram of circle a what is m

The graph of g(x) is a translation of y = which equation represents g(x)?