Acar is stopped at a traffic light. it then travels along a straight road such that its distance from the light is given by x1t2 = bt2 - ct3, where b = 2.40 m> s2 and c = 0.120 m> s3. (a) calculate the average velocity of the car for the time interval t = 0 to t = 10.0 s. (b) calculate the instantaneous velocity of the car at t = 0, t = 5.0 s, and t = 10.0 s. (c) how long after starting from rest is the car again at rest?

Arunner is jogging at a steady 3.6 km/hr. when the runner is 2.9 km from the finish line, a bird begins flying from the runner to the finish line at 14.4 km/hr (4 times as fast as the runner). when the bird reaches the finish line, it turns around and flies back to the runner. even though the bird is a dodo, we will assume that it occupies only one point in space, i.e., a zero-length bird. how far does the bird travel? (b) after this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. the bird repeats the back and forth trips until the runner reaches the finish line. how far does the bird travel from the beginning? (i.e. include the distance traveled to the first encounter)