I^15 = (i feel dumb for not knowing but i hate the i stuff, please solve)

Select all the correct answers. what is 221,000,000,000,000,000,000 expressed in scientific notation?

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?