Answers for these ?

The next 3 questions refer to the following: The table below shows a competitive firm's short-run production function. Labour is the firm's only variable input, and market price for the firm's product is $9 per unit. Labour Output 410 590 720 790 835 855 The 5th unit of labour adds $ to the firm's total revenue. If the wage rate is $190, the firm will employ units of labour. If market price for the firm's product decreases to $3, at the same wage rate of $190 the firm will earn a profit of $