100 A box contains 7 red marbles 4 white marbles, and 5 blue marbles. If only white marbles are added to the box, how many must be added to
make the probability of drawing a white marble ;
OA. I
OB 2
OC. 5
OD. 7
OE 12

Do one of the following, as appropriate: (a) find the critical value z subscript alpha divided by 2 , (b) find the critical value t subscript alpha divided by 2 . 99%; nequals 17; sigma is unknown; population appears to be normally distributed.