Ig i’ll give brainliest for someone lol

Plzzz answer both questions and i will give you 100 points

A+b= 17, ab=70, find the value of |a-b|

Aliaa is skating down a ramp. the wheels on her skateboard have diameters of 60 \text{ mm}60 mm60, space, m, m. what is the distance aliaa travels when her skateboard wheels make 202020 revolutions? round your answer to the nearest \text{mm}mmm, m.