could you help me with economics please?

[I Lost My Nickname!]

14) For which type of market structure can we calculate marginal revenue product of labor by taking marginal product times the price of the output?
A) monopolistic competition
B) monopoly
C) pure competition
D) all of the above

19) The demand curve for autoworkers is an example of a(n) ___ labor.
A) industry
B) geographic
C) aggregate
D) occupational

20) the demand curve for labor is:
A) downward sloping
B) perfectly inelastic
C) upward sloping
D) perfectly eleastic

[Cthulhu fhtagn!]

14.D (revenue is computed from price, so market structure does not matter

19 D, I guess

20 A. it's labor supply that might curve back