Tori experiments with pulleys in physics class. She applies 70 newtons of force to a single pulley to lift a bowling ball. By adding another pulley, she’d get a mechanical advantage of 2. What’s the minimum input force she’ll need to lift the ball if she adds another pulley? A.
2 N
B.
35 N
C.
68 N
D.
70 N
E.
140 N

4. multiple crosses were made between true-breeding lines of black and yellow labrador retrievers. all the f1 progeny were black. when these progeny were intercrossed, they produced an f2 consisting of 91 black, 39 yellow and 30 chocolate. a. propose an explanation for the inheritance of coat color in labradors. b. propose a biochemical pathway for coat color determination and indicate how the relevant genes control coat coloration.