Help ASAP please :()

Fiona races bmx around a circular dirt course. if the radius of the course is 70 meters, what is the total distance fiona covers in two laps of the race? a. about 30,772 meters b. about 15,386 meters c. about 879.2 meters d. about 439.6 meters e. about 219.8 meters23 points hurry

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

For what values of the variable x is the expression square root of 7x+14+ square root of 7-x a real number?