1) The acceleration of point A is defined by the relationship a=-5.4sin (kt), where a and t are expressed in ft/s and seconds respectively and k=3 rad/s. If point A starts with an initial velocity 1.8 ft/s at x=0 determine (a) The velocity of the body after 3 secs (b) Express the position of point A as a function of time, i.e. determine x(t) (20 pts)