The average starting salary of this year's graduates of a large university (LU) is $25,000 with a standard deviation of $5,000.Furthermore, it is known that the starting salaries are normally distributed.

How do I calculate the probability that a randomly selected LU graduate will have a starting salary of at least $31,000

20% of this year's graduates will have a starting salary that is higher than $_____

10 items were randomly selected from a large inventory and 25% of these items are made in Canada.

How do I calculate the probability that exactly 4 of the 10 items selected are made in Canada

How do I calculate the probability that at most 4 of the 10 items selected are made in Canada