Pls help me I really don’t know

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

Suppose m: angle a =77 degrees what is the measure of a complement of a complement of angle a, what is a conclusion you can draw about a complement of a complement of an angle

What is 10+10+20 about the origin the square root of a triangle.