Which process would correctly calculate the frequency of a wave? dividing speed by wavelength

dividing frequency by wavelength

multiplying frequency by period

dividing wavelength by period
SOMEBODY PLEASE ANSWER! This test determines my grade.

When a book falls from a shelf to the ground without anyone pushing on it, no work is done on the book. true or false

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2

Abag of potato chips contains 2.00 l of air when it is sealed at sea level at a pressure of 1.00 atm and a temperature of 20.0 deg c. what will be the volume of the air in the bag if you take it with you, still sealed, to the mountains where the temperature is 7.00 deg c and atmospheric pressure is 70.0 kpa? assume that the bag behaves like a balloon and that the air in the bag is in thermal equilibrium with the outside air.