The theorist you are talking about is none other than Abraham Maslow. He developed the Maslow's hierarchy of needs wherein basic human needs range from the physiological, security, and love and belongingness needs to the esteem and self-actualization of the individual.
The formula for acceleration is a = F/m; Where: F = force; m = mass
Given: F = .6n; m = .4kg; a = ?
a = F/m
= .6/.4
= 1.5
Therefore, the acceleration of the plate is 1.5 m/s^2
A) 1.55
The speed of light in a medium is given by:

where
is the speed of light in a vacuum
n is the refractive index of the material
In this problem, the speed of light in quartz is

So we can re-arrange the previous formula to find n, the index of refraction of quartz:

B) 550.3 nm
The relationship between the wavelength of the light in air and in quartz is

where
is the wavelenght in quartz
is the wavelength in air
n is the refractive index
For the light in this problem, we have

Therefore, we can re-arrange the equation to find
, the wavelength in air:
