Two tenths plus nine hundredths of a dollar

Which expression do you get when you eliminate the negative exponents of 4a^2 b^216a^-3 b

Eliza wants to make $10,000 from her investments. she finds an investment account that earns 4.5% interest. she decides to deposit $2,500 into an account. how much money will be in her account after 14 years?

Which is the focus of a parabola with equation y2=4x