To solve this problem we will apply the concepts related to the conservation of momentum. By definition we know that the initial moment must be equivalent to the final moment of the two objects therefore
![p_1 = p_2](https://img.qammunity.org/2021/formulas/physics/college/tfl51n26vfdgj22nfkup1ji097tjov4dov.png)
![m_1u_1+m_2u_2 = m_1v_1+ m_2v_2](https://img.qammunity.org/2021/formulas/physics/college/qxi0m3y2fw192mvzyko6wmkn9sd45t5zde.png)
Here,
Mass of each object
Initial velocity of each object
= Final velocity of each object
Since the initial velocity relative to the metal tank is at rest, that velocity will be zero. And considering that in the end, the speed of the two bodies is the same, the equation would become
![m_1u_1 = (m_1+m_2)v_f](https://img.qammunity.org/2021/formulas/physics/college/2cknd625iy5nzj99ke0na0vvo2ywac6fh9.png)
Rearranging to find the velocity,
![v_f = (m_1u_1)/( (m_1+m_2))](https://img.qammunity.org/2021/formulas/physics/college/qgxn4myqj43bj56jaeam1eyh9p0o3hd6ea.png)
Replacing we have that,
![v_f = ((332)(2.3))/( (332+19.5))](https://img.qammunity.org/2021/formulas/physics/college/c0xy2kaikogv1c46rvar1e2l94mtqa2chf.png)
![v_f = 2.17 m/s](https://img.qammunity.org/2021/formulas/physics/college/txr3zalhxymlreh1u35q65xsey2nq3h0ad.png)
Therefore the velocity of the shark immediately after it swallows the tank is
![2.17m/s](https://img.qammunity.org/2021/formulas/physics/college/a57o2org33q2is2fpvfmy2rzf6x7sk17q4.png)