$24.$ Lynn bought a $\backslash (\backslash$$ $300,000\backslash )$ house, paying $\backslash (10\backslash \%\backslash )$ down, and financing the rest at $\backslash (6\backslash \%\backslash )$ interest for $30$ years. a$.$ Find her monthly payments. b$.$ How much interest will she pay over the life of the loan?