Two cars traveled equal distances in different amounts of time. car a traveled the distance in 2 h, and car b traveled the distance in 1.5 h. car b traveled 15 mph faster than car a.

how fast did car b travel?

The answer is 60 mph.

The speed (v) is distance (d) per time (t): v = d/t

Car A:
v1 = ?
t1 = 2 h
d1 = ?
___
v1 = d1/t1
d1 = v1 * t1

Car B:
v2 = ?
t2 = 1.5 h
d2 = ?
___
v2 = d2/t2
d2 = v2 * t2

Two cars traveled equal distances:
d1 = d2
v1 * t1 = v2 * t2

Car B traveled 15 mph faster than Car A:
v2 = v1 + 15

v1 * t1 = v2 * t2
v2 = v1 + 15

v1 * 2 = (v1 + 15) * 1.5
2v1 = 1.5v1 + 22.5
2v1 - 1.5v1 = 22.5
0.5v1 = 22.5
v1 = 22.5/0.5
v1 = 45 mph

v2 = v1 + 15
v2 = 45 + 15
v2 = 60 mph

Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.

Lexy is correct because angle r is between the incident wave,  n  = 0, and a diffracted wave.