In a game being developed the x component of the velocity, v pixels/sec, of a moving element, at time t seconds from the start, is given by v=50+10 t-30 \sqrt{t}

(a) Given that the initial x coordinate of the moving element is 40 (pixels), use definite integration to find the x coordinate of the element after 4 seconds (b)Hence find the average velocity of the x component of the element in the first 4seconds