If each hexagonal mirror in the neck telescopes is 1.8 m across, how many mirrors would be needed to create a light-reflecting surface that is 10.8 m across?
a. 3.2
b. 5
c. 6
d. 6.2

i dont understand this..

Afamily has two cars. the first car has a fuel efficiency of 25 miles per gallon of gas and the second has a fuel efficiency of 15 miles per gallon of gas. during one particular week, the two cars went a combined total of 1025 miles, for a total gas consumption of 55 gallons. how many gallons were consumed by each of the two cars that week?