Chapter 8 Loop structures

Question 1

A Python while loop implements a definite loop.

Answer 1

False

Question 2

A sentinel loop should not actually process the sentinel value.

Answer 2

True

Question 3

What statement can be executed in the body of a loop to cause it to terminate?

Answer 3

Break

Question 4

identify the loop: asks the user whether to continue on each iteration

Answer 4

Interactive

Question 5

identify the loop: continues until a special value is input

Answer 5

Sentinel

Question 6

identify the loop: tests the loop condition after executing the loop body

Answer 6

post-test

Question 7

Briefly explain why the expression:

response[0] == “y” or “Y”

though a syntactically valid expression, always evaluates to True.

Answer 7

This will always evaluate as true because the statement after or ,”Y”, does not apply to the response[0] line it is just its own string. What this means is that it will allow any string that doesn’t begin with a lowercase “y” to be processed as True, because it is still a string.