5 A boy of mass 40 kg and a girl of mass 30 kg play on a see-saw of negligible weight. If the boy sits 270 cm from
the pivot of the see-saw, where must the girl sit to make it
balance?

Is the alien theory a scientific claim? why or why not? just took the test it was , : " the alien theory is not a scientific claim because it is not based on valid data, there is no evidence to support it, and it does not come from a reliable source."

Aball is thrown straight up into the air with a speed of 21 m/s. if the ball has a mass of 0.1 kg, how high does the ball go? acceleration due to gravity is g = 9.8 m/s^2. a. 22.5 m b. 20.0 m c. 25.0 m d. 17.5 m

Erosion of the beach is normally a slow process. however, in certain situations, large chunks of shore may wash out to sea. what could cause this to happen?