Hello Mubz, and welcome to PF.
Did you notice the omnipresence of the template ? Use it or else...

It's there for good reasons - read the guidelines.
We poor potential helpers are threatened with doom if we help those who don't use it - yet another good reason to use the template.
If you don't understand the above, take it for true on my authority.
Now to business, but only if you solemnly promise to ... use the template!
Nice table. His (her?) vaporative majesty's post and yours must have crossed. Doesn't take much to find an answer to his (/her) first question, right ?
To work out the original exercise, you will need to make a few complementary assumptions (at least, if they weren't already part of the formulation thereof):
1. "a rigid tank" is a closed vessel of fixed shape (does not deform under outside pressure)
2. "contains ..." means "contains ... and nothing else".
You will also need some relevant equations, but for the first part of the first question common sense is enough already. Here (and only here) you get away without equations.
Now item 3 from the template jumps in automatically: what choices do you have and which choice would be your best guess ?
Further help forthcoming - provided you catch up on this template stuff. Would have saved you (and me too) a lot of time if you had used it from the start! And there's another good reason to use the template!
Don't tell me you don't know what to do with the given table after reading the first line of the exercise. I will simply not believe it.
Afterward you can share your thoughts on why they threw in page 2 too. I can't find a reasonable explanation...