How do we know the frequency of a wave when we can't see it?

"I wanted the ideal animal to hunt," explained the general. "So I said, ‘What are the attributes of an ideal quarry?' And the answer was, of course, ‘It must have courage, cunning, and, above all, it must be able to reason.'" The word quarry has several different meanings. Which one is being used in the previous passage? a hunted animal a square or diamond shape open are for mining source

Which type of water is more dense: cold, salty water or warm, less salty water? Explain your answer

Organisms that can interbreed and produce offspring that can grow to produce young are of the same __________.

When a bus company trains bus drivers on a simulator, they are employing _____ training. A. substitute
B. vestibule
C. on-the-job
D. performance

Why can't plants and animals use the nitrogen directly from the atmosphere?Answer
A.There is not enough of it in the air.
B.Nitrogen gas contains the element in an inert, unusable state.
C.They do use it directly from the atmosphere.
D.Plants and animals do not need nitrogen for their life processes.

What is a nucleotide and a nucloeside?