Creating a simple Class Diagram

Question

Write a program that calculates the cost to send packages within the US. There are 3

different ways to send a package:

1. with UPS.

The cost to send a package with UPS is specified as follows:

Rate = $0.45 * number of pounds.

2. with US Mail.

The cost to send a package with US Mail is specified as follows:

If the weight is less than 3 pound, then the cost is $1.00.

If the weight is larger than 3 pounds, then the cost is $0.55 per pound.

3. with FedEx.

The cost to send a package with FedEx Mail depends on the zone where you send the 

package to and is specified as follows:

Total cost in dollars = zone * number of pounds where zone is specified as follows:

Zone = 0.35 for IA, MT, OR and CA

Zone = 0.30 for TX, and UT

Zone = 0.55 for FL, MA and OH

Zone = 0.43 for all others

The program should ask the user for a number of packages. For every package the user 

enters the package description, the weight and the zone. The program then calculates 

for every package the lowest price, and prints this to the screen together with the carrier 

name.

Example output:

Baby stroller $20.00 FedEx

Computer monitor $23.80 US Mail

Modem $5.60 US Mail

Make sure you program is open for extension, but closed for change. 

You succeeded in this lab when you can add a new carrier (for example DHL) without 

much code change, only code extension.

Also make sure you program to interfaces, rather than implementation.

Answer:

This is the class diagram of the problem. There may be others also as there is no one fixed method.