Pseudocode for Problem 3.4

Declare variables packageWeight and cost as doubles (initialize both to 0.0).

Prompt user to input the weight of the package.

Read in the weight of the package.

Check if the weight of the package is invalid and if so output error message.
(Note: consider outputting different messages for negative or zero as opposed to weight > 100 pounds--use nested if)

Do the following only if the weight of the package was valid
(use else clause of above if statement).

Any package up to two pounds costs $10 .
(cost <-- 10.0)

If package weight is more than two pounds, calculate additional cost as
$3.75 for each pound of fraction thereof over two pounds.
(cost <-- cost + ceiling(packageWeight - 2.0) * 3.75)

If package weight is more than 70 pounds, calculate additional cost.
(cost <-- cost + 10.0)

Output package weight and final shipping cost.