Q1) In the certain state, each automobile license plate number contains of 2 letters followed by the 4-digit number. How many distinct license plate numbers can be formed if:

(a) There are no restrictions and

(b) The letters O and I are not used?

(c) Determine the probability of choosing at random license plate which ends in the even number?

Q2) To conduct the Experimental, four subjects are arbitrarily chosen from the group of 20 subjects. How many different groups of four subjects are possible?

Q3) From the Group of 40 People, a jury of 12 people is selected. In how many several methods can a jury of 12 people be selected?