Please help I think I have an idea as to what it is but I think somethings off with what I got (Due in 8 minutes!! have a blessed day/night)

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

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

Full year - williamshow many square inches are in 60 square feet? 5 square inches72 square inches720 square inche8.640 square inches