Good Riddles

 
Riddle #172 (medium)

Question: No matter how hard you try,
I can open what you can't.
If it wasn't for me,
on your front porch you would stand.

What am I?

Riddle #3430 (medium)

By Sal

Question: What can you hear but not see?

Question: There are 57 ducks walking to a pond. On the way, 15 get lost, 26 head back, and 16 make it to the pond.

What happened to the rest?

Riddle #324 (medium)

Question: What temperature is twice as hot as 0 degrees Celsius?

Question: Three gods A, B, and C are called, in no particular order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter. Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one god. The gods understand English, but will answer all questions in their own language, in which the words for yes and no are da and ja, in some order. You do not know which word means which.

What three questions can you ask?