In need of branniest to anyone who awnsers

I’m stuck on this i don’t understand.

In the final round of trivia competition, contestants were asked to name as many states that begin with the letter m as they could in 15 seconds. the bar graph shows the number of states the contestants were able to name. how many contestants participated in the final round of the competition? a) 6 b) 8 c) 14 d) 20

What is the volume of a cone with a height of 6 cm in the radius of 2 cm