Consider the following statements regarding the differential of an automobile 1). The speed of the crown wheel will always be the mean of the speeds of the two road wheels 2). The road wheel speeds are independent of the number of teeth on the planets 3). The difference between the speed of the road wheels depends on the number of teeth on the planets 4). The ratio of speeds of the road wheels depends upon the number of teeth on the gear wheels attached to them and on the crown wheel Of these statements

(a) 1 and 2 are correct

(b) 3 and 4 are correct

(c) 1 and 3 are correct

(d) 2 and 4 are correct.