the output Q of a certain company can be modeled by Q=60 x^3/4 y^1/4, where x represents units of labor and y represents units of capital, all in billions of dollars

a. find the output of the company in billions of dollars if it spent $81 billion on labor and $16 billion on capital

b. Suppose that the output of the country is to be maintained at the level you found in part(a) by how much should the amount spent on capital be changed if the amount spent on labor is increased by $1 billion