What is the simplified form of the following expression? 2√27+√12-3√3-2√12

Henry is an avid reader, he devours 90 pages in half an hour how many pages has henry read per minute?

Don't know how to find x given these segment lengths

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document