8. mark can clean his father's office in 30 minutes. his younger sister lynn can clean the office in 40 minutes. how long will it take the two of them together to clean the office?

Aperpendicular bisector, cd is drawn through point con ab if the coordinates of point a are (-3, 2) and the coordinates of point b are (7,6), the x-intercept of cd is point lies on cd.

Koji is installing a rectangular window in an office building. the window is 823 feet wide and 534 feet high. the formula for the area of a rectangle is a=bh. what is the area of the window? enter your answer as a mixed number in simplest form in the box. $$ ft2

There were 25 students who answered to a survey about sports. four-fifths of them like football. how many students like football?