Which of the following quadratic functions has the widest graph?
a) y=1/3x^2
b) y=-4/5x^2
c) y=-4x^2
d) y=0.3x^2

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! "?