6.28 For the circuits in Fig. P6.28, assume that the transistors have very large ẞ. Some measurements have been made on these circuits, with the results indicated in the figure. Find the values of the other labeled voltages and currents. +12 V +10.7 V 5kf +0.7 V -2.7 V 5.6 kn 2.4 k -4V +10 V 9.1 ΚΩ 15kf 10 ko ww V₁ 20 ΚΩ 0.7v 0.7 V -10.7 V -10 V -10 V -10 V (a) (b) (c) (d)