need help with these thanks again.

The average weight of a simple of 35 apples from field A has a mean weight of 10 ounces and a standard deviation of 1.3 ounces. The average weight of a sample of 41 apples from field B has a mean weight of 10.7 ounces and a standard deviation of 2.3 ounces. What is the probabilty that the mean weights of apples from A will weigh more than that of apples from B?

On any given day, only 36% of the drivers who come to get gas at Nine-Eleven come to the store to buy a drink. If 400 cars are coming in today, what is the probability that at least 149 drivers will buy a drink?

Suppose, test 2 (that is, this test) scores are normally distributed. You don't know the class average u. But you know the standard deviation o = 10 from previous semesters. What'll be the minimum sample size for you to be able to create an 85% confidence interval for u which has a margin of error of + 2?

To assess the accuracy of a laboratory scale, a standard weight that is known to weigh 1 gram is repeatedly weighed a total of n times and the mean of the weighings is computed. Suppose the scale readings are normally distributed with unknown mean u and standard deviation 0 - 0.021 grams. How large should n be so that a 92% confidence interval for u has a margin of error of + 0.003?

The winter boots at The Right Format have an average cost of $70 with a standard deviation of $7. Assuming a normal distribution, what approximate Dollar amount separates the top 25% of the shoes from the lower 75% of the shoes?

There is a 25% chance a person will like the new movie Don't Round Off. Assume that 48 people are watching the movie right now. We want to know the probability that at least 16 of them will like it. If we use Normal approximation to the Binomial to answer this question, what z-score should we use?