A test of a printed circuit board uses a random test pattern with an array of 8 bits and each is equally likely to be 0 or 1. Write down the number of different bytes of possible different series.

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?