The highest point of a wave is called the crest. Among the choices, the correct answer is C. The height of the wave can be determined using the crest and the trough. The trough is the lowest point of a wave. The wavelength is the distance between two crests of a wave.
As radiation enters a solid or liquid, the light waves are absorbed and reflected by the atoms. the resulting reflection from an atom can be in any direction and is random. you can understand opacity in terms of the scattering of radiation. The more opaque, the more scattering.
(The truth is far more complicated than this, check out Richard Feynmans lectures on "Quantum Electro Dynamics" to learn the reality of it. )
You'll be using the equation f = m a, or force = mass x acceleration
First, you have to find the acceleration. The acceleration needed is the average acceleration over the 15 seconds is accelerated. So, you take the change in speed (25m/s - 15m/s) to get a change of 10m/s.
The average acceleration (acceleration per second) is found by dividing total acceleration by the time it took. So, it's 10 / 15, which equals .6. This is a, your acceleration
Now just plug it into the equation F = m a, because it already gives you the mass of the car
F = 550 x .6
Solve that to get F = 366.6. F is measured in Newtons (N), so your answer is 366.6N