Tell me why would it be hard to use volcanic eruptions or earthquakes to mark the start of periods? NO LINKS PLS

Suppose a suitcase has a mass of (m) 30 kg and a net force (n) of 10 kg*m/s. what is the acceleration rate of the suitcasein m/s? show your work to support your answer

Linda and julia are trying to determine whether their ideas are scientific or pseudoscientific. linda's idea is free of bias. julia's idea gives the same result when tested repeatedly. which statement is correct about linda and julia's idea?

What happens as electrons move along the chain of molecules known as the electron transport chain? they gain energy, which causes atp molecules to lose phosphate groups. they gain energy, which causes h *ions to join with oxygen to produce water. they lose energy, which is then used by the cell to make atp. they lose energy, which is then used to break down atp.