Please show complete work and how you got the solution

The figure shows a frame ABCD that is statically indeterminate to the second degree. Note that the plastic moment capacity is different for the three components of the frame.

a$.$ Identify the relevant failure mechanisms $($three in total$),$ and calculate the corresponding collapse loads expressed in terms of the plastic moment capacity and the parameter a$.$ Use the principle of virtual work and plastic hinges.

b$.$ Verify that the lowest collapse load from part a is correct by drawing the moment diagram $($on the tension side$)$ for the corresponding mechanism. Demonstrate that the plastic moment capacity is reached at the appropriate locations.

From the solution key: Lowest collapse load: Fp $=11$Mp$/24$a$.$

Please show how you calculate it