A CE amplifier has a resistor RF connected between collector

A CE amplifier has a resistor R_F connected between collector an d base R_F = 40 k. R_C = 4k. I f h_fe = 50, r_π = 1 k, then output resistance R₀ is _______ kΩ .

R₀ = R_L' = R_c ∥ R_p =	4 × 40	= 3.64 kΩ
	44

1 + β =	β R_C	= 50 ×	4K	=	50
	R_F + R_C		44K		11

1 + βA = D =	61
	11

R_of =	R₀	=	116	×	11	= 0.66 kΩ
	D		44		61