Hope uses the equation C = 3h + 9 to find the total cost, C, in dollars, of renting a bike for h hours. If Hope does not spend more than $30, what is the maximum number of hours she can rent the bike?

Abank manager wants to encourage new customers to open accounts with principals of at least $2,500. he decides to make a poster advertising a simple interest rate of 3%. what must the principal be if the bank manager also wants to advertise that one can earn $10 the first month? can the poster correctly say, "open an account of $2 comma 500 and earn at least $10 interest in 1 month! "?