2) Let X be the number of heads obtained in 40 independent tosses of a fair coin. Then V(X) = ? [2] 3) A large collection of tires has 3% defective tires. Suppose one chooses tires from this collection until he obtains 4 non-defective tires. Then calculate the mean of the total number of defective tires drawn in this process. [2] 4) If X~N(4,2) then Eng, X; ~ N(?, ?). [2]