Need help

It is hard for me

Write a degree 4 Maclaurin Polynomial for  

I need the last blank ... please explain how you answer that ..i was able to get A B and C ...

but I am having hard time answering the last blank .. plz help..

I just need the last blank ...please explain how you answer that .. i was able to get A B and C...but I am having hard time answering the last blank .. plz help..

and this prob please .. thanks in advance ...

can you help me with these problems i have such a hard time getting them and need help thank you so much

If anyone could help me, please, I would like to know how to sketch the isothermal curves of this function for the given values of T. The solution for this question doesn't show the step by step procedure for the final result; maybe it's easy for a lot of people but it's very hard for me.

Thank you in advance!