**Due Date:** Monday, September 17, or Tuesday, September 18,
2007, before the beginning of your lab section.

**Objective:** The main objective of this assignment is to practice
using input, output, arithmetic operations, and operations with strings.

**Programming assignment:** To protect students against rain, the
university decided to require every student to purchase a special
UTEP umbrella. These umbrellas comes in different size; the cost of
an umbrella is proportional to its area in square inches: 1 square
inch costs 10 cents, i.e., $0.10. Umbrellas are of the shape of a
half-sphere, so the area can be computed as 2 pi times the
umbrella's radius squared. Your program should estimate a cost of an
umbrella for a student and generate a bill. Specifically, your
program should:

- ask the student for his or her name;
- ask the student for the desired umbrella radius (in inches);
- print a bill with the student's name and the cost of the umbrella.

**Comment:** define Pi as a constant.

**Example:** Suppose that a student Carlos Acosta selects an
umbrella of radius 10.0 inches. Then, we compute the area as 2 *
3.141592 * 10.0^2 = 628.3184. The cost of this umbrella is then 0.1
* 628.3184 = $62.83.

*Comments:*

- do not worry about objects yet, just make it one main object;
- make variable names meaningful, so that it will be easy to read your program;
- add comments, so it will be clear what different statements do;
- add indentation as necessary, to make your program clearer.

**Homework assignment:** on a separate sheet of paper, solve Ex. 2
(p. 100), Ex. 10 (p. 102), and Ex. 12 (p. 103).

**Deliverables:** as instructed by your TA.