Need help with solving & understanding binomial/geometric questions.

3. A fair die has four faces numbered one to four. a. What is the probability of rolling a two exactly three times in ten rolls of the die? b. Find the standard deviation and expected number of 3's for ten rolls of the die? c. What is the probability of rolling the die 20 times and getting no more than 3 fours? 4. A packet of carrot seeds has a germination rate of 92%. In other words, the probability of any seed sprouting is 0.92. a. How many seedlings would you expect in a row of 50 seeds? b. What is the probability that exactly 4 seeds did not sprout? 5. 21% of the bolts produced by a machine are defective. a. Out of 6 bolts chosen at random, what is the probability that 2 are defective? b. What is the probability that the first defective bolt is the ist one chosen? c. What is the probability that the first defective bolt is among the 1st 4 chosen? 6. Statistical data indicates that 35% of all persons who are afflicted by a certain disease recover. What is the probability that 9 out of 10 patients selected at random recover? 7. There are 156 candidates taking a course. The probability that a candidate passes the course is 0.73 Find the probability that 2 out of 3 candidates chosen at random pass the course. 8. In a bombing attack there is 40% chance that any one bomb will strike the target. Two direct hits are required to destroy the target completely. What is the probability that the target will be destroyed, if only 3 bombs are dropped