Electrons in silicon carbide have a mobility of 1000 cm^2/V-sec. At what value of the electric field do the electrons reach a velocity of 3 X 10^7 cm/s? Assume that the movility is constant and independent of the elctric field. What amount voltage is required to obtain this field in a 5-micron thick region? How much time do the electrons need to cross the 5 micron thick region?