Pls solve this for 40 points and fast

Classify the following triangle check all that apply

Select all the correct answers. what is 221,000,000,000,000,000,000 expressed in scientific notation?

Problem fathi wants to print out a pdf document that is 48 pages long. to save paper, he decides to print on both sides of each sheet and to print two pages on each side of the sheet. how many sheets of paper will he need?