Determine the small-signal parameters for q1 q2 and q3

Question

Consider the series-shunt feedback circuit in given Figure, with transistor parameters: h_FE = 120, V_BE (on) = 0.7 V, and V_A = ∞.

(a) Determine the small-signal parameters for Q₁, Q₂, and Q₃. Using nodal analysis, determine:

(b) the small-signal voltage gain A_{v f} = v_o/v_i,

(c) the input resistance R_{i f}, and (d) the output resistance R_of.