Misc: what is the name of dennis the menace's dog?

Questions

What part of an eatery do some restaurant owners call "the cancer ward"?

What percentage of Earth's circumference does the Great Wall span?

What river snakes through Germany, Austria, Slovakia, Hungary, Serbia, Romania, & Bulgaria?

What sexually ambigious prisonmate was often dubbed "Mrs. Hitler"?

What shoe brand were all 39 members of the Heaven's Gate cult wearing when they committed suicide in 1997?