Discuss the fact that it is important to test for invalid input for the initial sentinel value when using while loops. How might you modify the code in Examples 5-4 and 5-5 to account for an invalid initial sentinel value? In other words, you would like the condition of the while loop to be tested at least once without input failure, and you would also like to avoid an infinite loop. Would initializing the sentinel variable during its declaration be helpful?

Draw the hierarchy chart and design the logic for a program that calculates service charges for hazel's housecleaning service. the program contains housekeeping, detail loop, and end-of-job modules. the main program declares any needed global variables and constants and calls the other modules. the housekeeping module displays a prompt for and accepts a customer's last name. while the user does not enter for the name, the detail loop accepts the number of bathrooms and the number of other rooms to be cleaned. the service charge is computed as $40 plus $15 for each bathroom and $10 for each of the other rooms. the detail loop also displays the service charge and then prompts the user for the next customer's name. the end-of-job module, which executes after the user enters the sentinel value for the name, displays a message that indicates the program is complete.

How can a user delete a drawing object

The volume v and paper surface area a of a conical paper cup are given by where r is the radius of the base of the cone and h is the height of the cone. a. by eliminating h, obtain the expression for a as a function of r and v. b. create a user-de ned function that accepts r as the only argument and computes a for a given value of v. declare v to be global within the function. c. for v ! 10 in.3 , use the function with the fminbnd function to compute the value of r that minimizes the area a. what is the corresponding value of the height h? investigate the sensitivity of the solution by plotting v versus r. how much can r vary about its optimal value before the area increases 10 percent above its minimum value?