The rays OM , ON , and OP in the figure, coincide at time t=0. At the same instant of time OM and OP rotate in the plane about point O in opposite directions while ON remains fixed. With respect to ON , segment OM rotates at constant rate of 3° per second and OP , at 6° per second. What is the smallest positive value of t, in seconds, for which segments OM and OP will coincide? When t=30 min, how many more revolutions does segment OP complete than segment OM ?