Need halp with this math problem by i mean the answer.

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?

Acone with volume 1350 m³ is dilated by a scale factor of 1/3. what is the volume of the resulting cone? enter your answer in the box. m³

How do you solving the solution of each system using elimination?