Courier Rates for Delivery of Mail Up to 200 G

Multiple Choice

Courier rates for delivery of mail up to 200 g are given in the following chart:
Draw the graph of the cost (in dollars) of mailing a letter as a function of its mass (in grams) . Where are the discontinuities of this function? Is the cost function right or left continuous at these points?

A) discontinuous at 30, 50, 100; left but not right continuous there
B) discontinuous at 30, 50, 100; right but not left continuous there
C) discontinuous at 30, 50, 100; neither left nor right continuous there
D) There are no discontinuities.
E) discontinuous at 30, 50, 100; right continuous at 30 and 50, left continuous at 100