What type of simple machine is used to raise a flag on a flag pole? . . a.. wheel and axle. . b.. lever. . c.. pulley. . d.. wedge

C. Pulley

Explanation:

A pulley is a simple machine used to raise an object against the gravitational force. It can be used to lift heavy things as well.

When we raise a flag, a pulley is attached at the top of the rod/pillar. Through that pulley a rope is attached along with flag. As the rope is dragged downwards, the flag lifts up.

Same theory is applied while taking water out from a well.

sonar - device which is used to find the submit submarines, sankalp ship. sonar waves consists of a transmitter and detector which are installed in the observation centre on board of a ship. the ultrasonic waves are sent into the sea at high frequency about 1000 khz in all direction.

answer: option c.

explanation: