A car that travels 20 miles in \frac{1}{2} 2 1 hour at constant speed is traveling at the same speed as a car that travels 30 miles in \frac{3}{4} 4 3 hour at a constant speed.

Step-by-step explanation:

If distance is 20 miles and time is (1/2) h. Its speed is given by :

If the distance is 30 miles and the time is (3/4) hours. Its speed is given by :

So, the rate or the speed ib both the case is constant.

a. she will receive a refund of $278.

step-by-step explanation:

since no one answered yet i will give it a shot, not completely sure tho.

i think it should be y=cos(x+2pi), (third answer, answer c)

good luck.