An antiproton (same properties as a proton except that q = -e) is moving in the combined electric and magnetic fields of the figure below, in which 1050 V/m is the magnitude of the electric field (directed down) and 466 m/s is the antiproton's speed (to the right). (a) What are the magnitude and direction of the antiproton's acceleration at this instant? m/s2 (b) What would be the magnitude and direction of the acceleration if were reversed? m/s2