Number 5 is A
number 6 is D
Imagine a car, and imagine you see little arrows below and beneath it, just around it. <span>The path of a particle that is flowing steadily and without turbulence in a fluid past an object.</span>
Answer:
50 N/m
Explanation:
Elastic energy = kinetic energy
EE = KE
½ kx² = ½ mv²
½ k (4 m)² = ½ (8.0 kg) (10.0 m/s)²
k = 50 N/m
A) 
The energy of an x-ray photon used for single dental x-rays is

The energy of a photon is related to its wavelength by the equation

where
is the Planck constant
is the speed of light
is the wavelength
Re-arranging the equation for the wavelength, we find

B) 
The energy of an x-ray photon used in microtomography is 2.5 times greater than the energy of the photon used in part A), so its energy is

And so, by using the same formula we used in part A), we can calculate the corresponding wavelength:

The term is frequency.
The frequency is the number of vibrations per unit of time or the number of waves that passes a point per unit of time.
Every crest (and every trough) represents a pass of the wave so you can count the number of crests in an intervavl of time to find the frequency as the number of crests divided by the time elapsed.