An interior designer makes a presentation to potential clients and this results in sales of her services in 35% of the cases. Let X denote the number of sales in the next four presentations. Assuming the results for different clients are independent, calculate the probabilities f(x) = P [X= x] for x= 0,1,...4 and find
a. P[X < 3]
b. P[X > 3]
c. P[X = 2 or 4]