which of the following was an achievement of the harappan civilization, the earliest known group in the indus valley?
a.
the elevator
b.
indoor drainage
c.
windmills
d.
refrigeration

b b b b b b b b b b b b b b b b b b b b b b bb bb bbb b bb bbb b b bbb bb b bb

Explanation:

under god i have placed my chiest strentgh and the safe guard to my loyal subjects

incident infrared radiation is blocked. visible and ultraviolet radiation heat   earth.

earth radiates infrared radiation. infrared radiation is blocked and heats earth. visible and shortwave radiation heat earth.

earth radiates longwave radiation

longwave radiation is reflected downward longwave radiation heats earth