Answer: D; 360
Step-by-step explanation: To find percentages, I like to set up proportional relationships to find the amount. It would look like this:
=

90= part %
100= whole %
?= amount of the %
400= all of the item(s)
So, we would cross multiply the 90 and the 400, then divide it by 100. That would be 36,000. So, that divided by 100 leaves us with 360. I hope this helped!