Another free points thing bc im kind today, have a great day! also first to answer gets brainliest

Explain vector addition, triangle method and parallelogram method

Will give brainliest! jay rides his 2.0-kg skateboard. he is moving at speed 5.8 m/s when he pushes off the board and continues to move forward in the air at 5.4 m/s. the board now goes forward at 13 m/s.a. determine jay’s mass.b. determine the change in the internal energy of the system during this process.(express your answer to two significant figures and include the appropriate units.)

Which sound characteristic is not affected by the relative motion of an object