The demand equation for the Roland portable hairdryer is given as follows where x (measured in units of a hundred) is the quantity demanded per week and p is the unit price in dollars. Is the demand elastic or inelastic when p = 5?

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.