Please help with this fast

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

The domain of a function can be represented by which one of the following options? o a. a set of output values o b. a set of f(x) values o c. a set of input values o d. a set of both input and output values

Ashley spent half of her lunch money on a turkey sandwich. then she spent two-thirds of the money she had left on a bottle of juice and the rest of the money on a cookie. if the cookie cost $.75, how much lunch money did ashley have to start with?