Answer:
It can be seen from the operation of pin-hole camera, formation of shadows and eclipse.
Explanation:
The phenomenon of light traveling in a straight line is known as rectilinear propagation of light.
One this evidence can be seen from the operation of pin-hole camera, which depends on rectilinear propagation of light
Also two natural effects that result from the rectilinear propagation of light are the formation of Shadows and Eclipse.
An object can be at rest and still be in motion because the earth is always in motion.
It is the branch of science, in which we study different phenomena of atmosphere including climate and weather.
Answer:
The curl is 
Explanation:
Given the vector function

We can calculate the curl using the definition

Thus for the exercise we will have

So we will get

Working with the partial derivatives we get the curl

Transverse, I think. I may be wrong.