A stone is dropped from the roof of a building 640 feet above the ground. The height of the stone(in ft) X seconds is given by H(x)=640-16 To the power of two
Find the instantaneous velocity X=2
Find the velocity x=a

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.

what i would say the best answer is a. 40.5

i am not sure :

step-by-step explanation: