4 How many different ways can four Presidents and Vice Presidents stand in a line for a picture if:
a) There are no restrictions?
b) Every President and Vice President must stand together?
c) There must be four Presidents in the middle four positions?
Can anyone help me?

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Find the missing dimension! need asap! tiny square is a =3025 in ²

Jim had 3,067.48 in his checking account he wrote a check to pay for two airplane tickets. his account now has 1,845.24.