On a number line what is the distance between _3/7 and _ 2/3?

Mr. brettler is hanging up a 5-foot tall rectangular welcome sign in the gym. he has drawn a sketch on a coordinate grid. he has the lower vertices of the sign at (9, –3) and (–6, –3). where would the upper vertices be on the grid?

Someone me i need with this stuff

Which radical expression is a rational number? a. √ 360 b. √ 644 c. √ 225 d. √ 122