In the above figure, the slope at point b

The table above shows a total product schedule. Suppose that labor costs $20 per worker and fixed costs are $60. The total variable cost of producing 80 units equals

A) less than $50. B) more than $50 and less than $70. C) more than $70 and less than $90. D) more than $90 and less than $120. E) more than $120.

What can be concluded from Milton Friedman and Edmund Phelps' expectations-augmented Phillips curve?

A) that there is no long run tradeoff between unemployment and inflation B) that there is a short run tradeoff between unemployment and inflation C) that there are two types of Phillips curves D) all of the above E) none of the above