Oil is flowing through a 4-inch diameter pipe having a velocity of 6 ft/sec. The flow rate gallon per minute and kinetic energy of water in (ft)(lbf)/(lbm) are respectively?

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.