Select the correct answer.

A car moves with an average speed of 45 miles/hour. How long does the car take to travel 90 miles?

A

2 minutes

B.

2 hours

C 45 minutes

D. 45 hours

E.

90 minutes

Rachel is running at 5 m/s when she suddenly gets a cramp and slows down to 1 m/s. if her acceleration was - 50 m/s^2, how long did it take her to slow down?

Suppose that a person has an average heart rate of 72.0 beats/min. How many beats does he or she have in 2.0 y? In 2.00 y? In 2.000 y?

Now the elevator is moving downward with a velocity of v = - 2.8 m/s but accelerating upward with an acceleration of a = 5.5 m/s2. (Note: an upward acceleration when the elevator is moving down means the elevator is slowing down.

Radiocontrast dyes are considered safe because the isotopes have short half-lives and the isotopes coat the gastrointestinal tract and are not absorbed by normal tissue. If a patient ingests 10.

you drive in a straight line at 20.0m/s for 10.0 min, then 30.0m/s for another 10.0 min. Find the average speed.

Which of the following is not shorthand to describe one of the three types of ecological relationships? +/+ -/+ +/0 -/0

Which is a characteristic of an electromagnetic wave?

What does the ozone layer absorb? a. Microwaves c. UV radiation b. X-rays d. Infra-red radiation

An object is undergoing shm with period 0.900 s and amplitude 0.320 m. at t = 0 the object is at x = 0.320 m and is instantaneously at rest. calculate the time it takes the object to go (a) from x = 0.320 m to x = 0.160 m and (b) from x = 0.

Your friend states in a report that the average time required to circle a 1.0-mi track was 49.325 s. This was measured by timing 10 laps using a stopwatch with a precision of 0.01 s. Do you believe his results are reliable? Explain.