Four buses carrying 156 high school students arrives in Montreal. Buses carry, respectively, 30, 49, 33, and 44 students. One of the students is arbitarily selected. Let X denote number of students which were on bus carrying this arbitarily chosen student. One of 4 bus drivers is also arbitarily chosen. Let Y denote number of students on his bus. Calculate expectations and variances of X and Y:

E(X)=
Var(X)=
E(Y)=
Var(Y)=