Answer:

who cast a shadow to whom?

• To cast a shadow you need an object that can block light rays. Not every object is able to do that. Some materials will let the light pass through whereas others will only block some of it. Objects able to block all the light are called opaque and will form a shadow.

• The sun casts shadows that change dramatically through the day. The length of a shadow cast on the ground is proportional to the cotangent