How many seconds will be required for a car traveling at 34 ft/sec to come to rest if it is decelerating at 2.5 ft/sec/sec? Use formula: a = Vf - Vi / t

What do the atoms of elements in the same group have in common? a. they have the same atomic numbers. b. they have the same average atomic masses. c. they have the same number of electron shells. d. they have the same number of electrons in their outermost shells.