What is the displacement from t=0s to t=4s

Isla’s change in velocity is 30 m/s, and hazel has the same change in velocity. which best explains why they would have different accelerations? isla had negative acceleration, and hazel had positive. isla had a different time than hazel. isla had positive acceleration, and hazel had negative. isla went a farther distance than hazel.

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?

How many neutrons does plutonium -196 with an atomic number of 78.