2. Suppose we have a pnp BJT made of Si. In terms of doping concentration, the emitter has 10¹⁹ cm³³,the base has 10¹8 cm³, and the collector has 10¹7 cm³. All plots should assume the emitter is on the leftside. For this problem, we apply various voltage biases. (a) Draw the energy band diagram assuming VBE = 0 V, VCE = 0 V. Label the following: EF, Ec, Ev, qVBE,qVBC. Keep the depletion region widths from (1c). What mode is the BJT in? (b) Draw the energy band diagram assuming VBE = -0.7 V, VCE= - 5 V. Label the following: E₁, Ec, Ev,qVBE, qVBC. Change the depletion region widths from (2a). What mode is the BJT in? (c) Draw the energy band diagram assuming VBE = -0.7 V, VCE0 V. Label the following: E₁, Ec, Ev,qVBE, qVBC. Change the depletion region widths from (2a). What mode is the BJT in?