These answers are obviously correct but they represent the brute-force approach. Nothing wrong here but considering all these lines, it is likely that mistakes or typos get in the way of the correct answer. Furthermore, the final expression does not give insight in case a design goal exists: what is the mid-band gain?
An easier approach consists of using the fast analytical techniques or FACTs. Just draw little sketches and read the resistance driving capacitors \$C_1\$ and \$C_2\$ to determine the time constants of the circuit. The below drawing shows the steps, you can't beat this in terms of simplicity : )
Once you have the time constants, assemble them following the below Mathcad file and you obtain the transfer function. Unveil the resonant frequency and the quality factor, rearrange and you have a transfer function in which the mid-band gain clearly appears.
Finally, the dynamic response is given below, confirming the 12-dB attenuation in the flat magnitude portion:
Determining a transfer function is one thing and many paths lead to the correct expression. However, what matters at the end is to shape the expression into a meaningful form that you can exploit to fulfill your design goals. The FACTs are truly unbeatable in terms of execution speed and the delivery of low-entropy expressions. Vive les FACTs ! : )