No...........................................................................Work for them urself
acceleration = change in velocity/change in time
so...
a = 20 m/s / 2 seconds
a = 10
hope that helps :)
P.S. found this from Brainly User, sometimes all you have to do is search to find the answer.
Answer: 0.169 (3 s.f.)
Explanation:
Force = 76 N
Spring constant = 450 N/m
Extension/displacement = x
Hooke's law states that: F = kx
Therefore, 76 = 450 X x
76/450 = x
0.169 (3 s.f.) = x
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:
