Front Cover:

Humayun's tomb, New Delhi. Photo courtesy Wikipedia.

Back Cover:

Spider's Web. Photo by Derek Nelson, https://facultypages.scad.edu/~mkesson/vsfx705/wip/best/winter08/derek_nelson/Spider_Web.html

Front inside cover:
Global Warming: Cartoon

Back inside cover: (Please move this caption to back inside cover)

Photo illustrates Newton's First Law, also called Galileo's Law of Inertia. The truck, which was carrying a heavy, massive stone slab, suddenly braked. Since the slab was not bolted down, it kept moving forward and collided with the front part of the truck! Photo from https://sillyscientists.wordpress.com