I know for a fact the answer is D. the distance traveled by the wave during one full cycle
C. This is the idea of "black body radiation". Charcoal/carbon is a "perfect black body". Absorbs all radiation. There's a whole host of stuff about this in physics, including, I think, Planck's (Nobel Prize winner) black body radiation theory.
Explanation:
Given that,
The force exerted by the stick on the puck is 975 N
The stick is in contact with the puck for 0.0049 s
Initial speed of the puck, u = 0 (at rest)
(a) We need to find the impulse imparted by the stick to the puck.
Impulse = Force × time
J = 4.7775 kg-m/s
(b) Mass of the puck, m = 1.76 kg
We need to find the speed of the puck just after it leaves the hockey stick.
Let the speed be v.
As impulse is equal to the change in momentum.

So, when the puck leaves the hockey stick its speed is 2.86 m/s.
Given Information:
Mass = m = 20000 kg
Height of ramp = h = 0.840 m
Length of ramp = L = 20 m
Required Information:
Uphill Force = F = ?
Answer:
F = 8232 N
Explanation:
The force can be found using the equation
F = mgsinθ
Where m is the mass of block, g is the acceleration due to gravity
Since the ramp can be modeled as an inclined plane so it can formed into a triangle, recall that in right angle triangle sinθ is equal to opposite over hypotenuse. The opposite is the height and hypotenuse is the ramp surface.
sinθ = h/L = 0.840/20 = 0.042
F = 20000*9.8*0.042
F = 8232 N
Therefore, an uphill force of 8232 N would be needed.