If a current of 2 amps is moving through a circuit connected to a 9 v battery, what is the resistance of the circuit? ? 4.5 ohms 18 ohms 0.2 ohms 7 ohms i think that the answer might be d because 9-2 is 7? but i really don't know, if someone could explain how they got their answer that'd be great. millions.

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e

Ireally need this answer sombody fast fast

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.