how to solve this problem

Given that a box has 4 blue marbles, 3 red marbles, and 5 yellow marbles, use the probability formulas to answer the following questions. Reduce all fractions. Use / as the fraction bar and do not use any spaces. What is the probability of... 1. Drawing a blue marble? P B 1/3 2. Drawing a marble that is not red? PC R' 3/4 3. Drawing a red and yellow marble at once? PC RUY + 0 4. Drawing a red or blue marble. P( R | B + 7/12 5. Drawing a red marble, put it back, and then drawing a yellow marble P( BOY + 5/48 6. Drawing a yellow marble, keeping it, and then drawing another yellow marble? PC YUY + )= 5/33