Answer:
B: Amplitude
Explanation:
When a wave travels from one medium to the other from an angle, the things that change are amplitude, wavelength, intensity and velocity.
The frequency doesn't change because the frequency depends upon the source of the wave and not the medium by which the wave is propagated.
Answer:
The equation of motion is 

Explanation:
Lets calculate
The weight attached to the spring is 24 pounds
Acceleration due to gravity is 
Assume x , is spring stretched length is ,4 inches
Converting the length inches into feet 
The weight (W=mg) is balanced by restoring force ks at equilibrium position
mg=kx
⇒ 
The spring constant , 
= 72
If the mass is displaced from its equilibrium position by an amount x, then the differential equation is



Auxiliary equation is, 

=
Thus , the solution is 

The mass is released from the rest x'(0) = 0
=0


Therefore ,

Since , the mass is released from the rest from 4 inches
inches
feet
feet
Therefore , the equation of motion is 
The answer is either c or d but c is the best answer
The answer, using an indicator to measure the hydrogen ion concentration of a solution, is correct
Data is inappropriate
here, we need gauge of the wire i.e., diameter of the wire, so that we calculate the resistance by using the formula
R = ρl/A
where R= resistance ; Ω
l = length of wire ; m
A = area of wire ; m²
ρ = resistivity ; Ω-m
But in general ohms law is
V = I R
R = V/I ;
but here we also calculate "R" from length of wire in which the current is flowing.
I hope it is helpful to you.