A skateboarder is skating through a dip at a constant speed. He remains in contact with the road at all times. What is an equation for the normal force acting on the skateboarder when he is at the bottom of the dip, in terms of the total mass of the skateboarder and skateboard, m, and the acceleration of the skateboarder, a? Neglect drag and friction.
a. mg
b. ma
c. m(g-a)
d. m(g+a)