Which statement is true about wind energy? a) it is clean and non-polluting. b) it is only effective near water. c) it is costly and hard to produce. d) it is not as useful as fossil fuels.

This is the substance(s) formed in a chemical reaction.

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?