T = k/R where k is the constant of variation, T=time and R=speed.
Plug in the given values:-
12 = k/60
k = 12*60 = 720
So the equation of variation is T = 720/R
At 85 mph we have
T = 720 / 85 = 8.47 hours (answer)
Light travels 5,580,000 mi/s in thirty seconds
If you have stood in front of a fireplace or near a campfire, you have felt the heat transfer known as radiation. The side of your body nearest the fire warms, while your other side remains unaffected by the heat. Although you are surrounded by air, the air has nothing to do with this transfer of heat. Heat lamps, that keep food warm, work in the same way. Radiation is the transfer of heat energy through space by electromagnetic radiation.
Circumcerence = distance travelled in one full rotation = 2 x π x 8 = 16π
for 2 minutes and 15 seconds,
multiply 16π by 2.25 as 2 minutes is twice the distance of one rotation and 15 seconds is a quarter more
therefore answer is 36π = 113.1 inches
