During what 2 seconds time period is the sketeboarder traveling the fastest

How would doubling the made of an object change the objects potential energy

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present

Which is an example of an exothermic process?