Answer:
Option c that it means cm/year.
Explanation:
Nm means nanometer, 1x10^9m
Km/s^2 is acceleration
h.. it may be height
Answer:
shadow length 7.67 cm
Explanation:
given data:
refractive index of water is 1.33
by snell's law we have


solving for



from shadow- stick traingle


s = 19tan22 = 7.67 cm
s = shadow length
Well for starters, gravity keeps things down on Earth. Also, gravity applies its force on to cars to maintain stability by forcing the tires to make constant contact to the ground creating friction between the rubber and road surface allowing the car to be moved. I'm sure someone else has better ideas!