slider crank mechanism

Question

1. In an off-set slider crank mechanism, shown in figure, the crank is rotated at a constant speed of 150 rpm. The value of the angle è shown in the figure is 20⁰. What is the ratio of forward to return stroke time? Can this mechanism be used in the application involving quick return?                                                                  

      (a) 3.33, No                                                        (b) 0.73, yes

        (c) 1.25. yes                                                     (d) 0.73, No