3. [3i] points] Consider a i-D cross-eld accelerator with small Hall parameter (:2 { 1), the advantageous strategy to maximize the velocity gain would he to program the electric and magnetic elds in the accelerator to retain the product {it 5X11 n) at its (negative) maximum at each location of the accelerator, since this maximizes the velocity increment at each location. Demonstrate that this condition is achieved if E and B-elds are chosen at each accelerator's location so that: a 2y1 B'zol)" (H