Please help I’ll give brainliest

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.

Natasha spent 1 1/2 hours on the beach. she fell asleep for 3/4 of the time she was on the beach and then woke up with a terrible sunburn. how many hours was natasha asleep on the beach?

Question and answers are in the attached picture. you so much in advance.