For each case, list the values of x and P (x) and determine if the specification represents a probability distribution. If it does not, state what...

1. For each case, list the values of x and P(x) and determine if the specification represents a probability distribution. If it does not, state what properties are violated. 

a.  for x = 3, 4, 5, 6 

b.  for x = 1, 2, 3, 4 

c.   for x = -2, -1, 0, 1, 2 

d.   for x = 2, 3, 4, 5