Find dy/dx. 7) y = Vx - 4 Vx + 4 7) A) - VX ( V X + 4 ) 2 B) - 8 x +4 C) - (x + 4)x - 16 D) - - ~x ( VX + 4) 2 Find the fourth derivative of the function. 8) y = 3x3 + 4x2 - 5x 8) A) 0 B) 9x +18 C) 18 D) 9 Solve the problem. 9) The dollar revenue generated by the sale of x bicycles is given by R(x) = 50.00x - x2/200. Find the 9 ) marginal revenue when ( Find R (x ) x = 500 units. A) $55.00 B) $10.00 C) $45.00 D) $50.00 The figure shows the velocity v of a body moving along a coordinate line as a function of time t . Use the figure to answer the question. 10) v (ft/sec) 10) t (sec) -1+ -2+ -3+ 4+ When is the body's acceleration equal to zero? A) t = 2, t = 3, t = 5, t = 6 B) t = 0, t = 4, t = 7 C) 0