Physics
Which layer of the earth's atmosphere reflect back the radio waves to the earth's surface ?

Ionosphere
Exosphere
Stratosphere
Mesosphere

ANSWER DOWNLOAD EXAMIANS APP

Physics
What is a compound microscope?

A microscope whose lenses are concave.
A microscope that has two sets of lenses : an occular lens and an eyepiece.
A microscope that has one lens.
A microscope whose lenses are convex.

ANSWER DOWNLOAD EXAMIANS APP