I think it is D but im not sure
Sound is all about vibrations.
The source of a sound vibrates, bumping into nearby air molecules which in turn bump into their neighbours, and so forth. This results in a wave of vibrations travelling through the air to the eardrum, which in turn also vibrates.
Answer:
B 5.0 A
.
Explanation:
Hello.
In this case, since we know the charge (1200 C), time (4 min =240 s) and resistance (10Ω) which is actually not needed here, we compute the current as follows:

Then, for the given data, we obtain:

Therefore, answer is B 5.0 A
.
Best regards!
Answer: The ice cube would float on top of the water and the rock would sink to the bottom.
Explanation: The ice cube has a smaller density than the rock which allows the ice cube to float but makes the rock sink to the bottom of the glass of water.
Answer:
3 kg
Explanation:
Momentum before = momentum after
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
After jumping on the skateboard, the student and the skateboard have the same velocity, so v₁ = v₂.
m₁u₁ + m₂u₂ = (m₁ + m₂) v
(47.4 kg) (4.2 m/s) + m (0 m/s) = (47.4 kg + m) (3.95 m/s)
m = 3 kg