If Katrina runs at a pace of 3 mph how many miles can she run in 2 hours

When keisha installed a fence along the 200 foot perimeter of her rectangular back yard, she left an opening for a gate.in the diagram below, she used x to represent the length in feet of the gate? what is the value? a. 10 b. 20 c. 25 d. 30

Can some one me with these questions

Find the domain of the following expression: 1/(√x)-2