Answer:
C ) 1.53
Explanation:
The critical angle of a material is given by the formula

where
c is the critical angle
n is the refractive index
This formula is valid if the second medium is air (which is the case of the problem).
In this problem, we know the critical angle:

Therefore we can rearrange the equation to find the refractive index:

During either one, the sun, moon, and Earth are lined up in the same straight line. The difference is whether the moon or the Earth is the one in the "middle".
The correct answer to the question above is hypertonic. When celery is being placed in a glass of pure water, the solution inside its cells is going to appear as hypertonic compared to the water. This means that the cells inside has a higher concentration than outside.
Work formula:

F = 50N, d = 1.0 m
When you lift something straight up, the angle of the force is 90º
cos(90º) is 0, so there's no work done when you lift the microwave off the ground

F = 50N, d = 1.0 m
When you push the microwave, the angle is 0º and cos(0º) is 1. So there is work done here:


total work = 50 joules