Consider the bias circuit shown in Figure P13.10. Let V+ = 3V,  V–, = –3V, R1 = 80kΩ, and...

Consider the bias circuit shown in Figure P13.10. Let V+ = 3V,  V–, = –3V, R1 = 80kΩ, and RE = 3.5kΩ. Assume transistor parameters of Is = 5 × 10–15 A for Q1, Q2, Q3, Is = 3 × 10–15 A for Q4; and Is = 10–15 A for Q5. (a) Find the currents Iref, I3, I4, and I5. (b) Repeat part (a) for Is = 8 × 10–15 A for Q4 and Is = 2 × 10–15 A for Q5.