Q9. Find the input pole

For the amplifier below, determine the input pole frequency (in rad/s). Note that the transistors are identical and have the values, C_{\mu} = 0.5 pF,  and the transition frequency f_T = 400 MHz. The C_{\mu} and C_{\pi} obey the relation C_{\mu} + C_{\pi} = \frac{g_m}{2\pi f_T}. Assume that the 0.4mA current source provides 0.2mA current to each transistor at bias conditions.