I need help wiht math

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

Someone answer asap for ! a discount store’s prices are 25% lower than department store prices. the function c(x) = 0.75x can be used to determine the cost c, in dollars, of an item, where x is the department store price, in dollars. if the item has not sold in one month, the discount store takes an additional 20% off the discounted price and an additional $5 off the total purchase. the function d(y) = 0.80y - 5 can be used to find d, the cost, in dollars, of an item that has not been sold for a month, where y is the discount store price, in dollars. create a function d(c(x)) that represents the final price of an item when a costumer buys an item that has been in the discount store for a month. d(c(x)) =

Which question is not a good survey question? a. don't you agree that the financial crisis is essentially over? 63on average, how many hours do you sleep per day? c. what is your opinion of educational funding this year? d. are you happy with the availability of electronic products in your state?