Which long division problem can be used to prove the formula for factoring the difference of two perfect cubes?
a) a-b square root a2+ab+b2
x b) a+b square root a2-ab+b2
c) a+b square root a3+0a2+0ab2-b3
d) a-b square root a3+0a2+ab2-b3

Abank manager wants to encourage new customers to open accounts with principals of at least $2 comma 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! "?