Medium.
Medium is matter, and electromagnetic waves do not need matter to travel. Just like the sun, its plasma light travels across space to reach us.
When a star is moving away from earth it appears blue
Answer:
3.38 m/s
Explanation:
Mass of child = m₁ = 25
Initial speed of child = u₁ = 5 m/s
Initial speed of cart = u₂ = 0 m/s
Mass of cart = m₂ = 12 kg
Velocity of cart with child on top = v
This is a case of perfectly inelastic collision

Velocity of cart with child on top is 3.38 m/s
When light passes through one transparent medium to another transperent medium it bends and that beding of light is know as refraction of light !
Answer:
213 s
Explanation:
Slope is the ratio of change in vertical distance to change in horizontal distance.
Slope = vertical height / horizontal height
Therefore:
6.4% = vertical height / 12.42
vertical height = 6.4% * 12.42
vertical height = 0.8 miles
The distance travelled by the car (s) is:
s² = 0.8² + 12.42²
s² = 154.9
s = 12.45 miles
Acceleration (a) = 2.93 ft/s^2 = 0.00055 mile/s²
initial velocity (u) = 0, final velocity = 203 mph
Using:
s = ut + 0.5at²
12.45 = 0.5(0.00055)t²
t =213 s