Abaseball of mass m = 0.16 kg is suspended vertically from a tree by a string of length l = 1.4 m and negligible mass. take z as the upward vertical direction. a short-duration force f = fyj + fzk is applied to the baseball by a bat, momentarily creating a torque τ about the top of the string. enter an expression for the torque due to the given force about the top of the string, in terms of m, l, fy f , and the unit vectors i