Answer:
The hook should be in the intro paragraph, usually being the first or second sentence.
Step-by-step explanation:
This is because, when writing an essay, especially an informational essay, you want the reader to be interested in the essay they are reading from the get go. You could start with a quote from someone famous or even a popular book/magazine, concerning what you are going to write about; you could even make something up, though it must be clever.
Hope this helps you out!
Have a great day! ;)