the first one is 8.5m2 + 2.2n ,, then the other person had the rest right . and number 3 could be 3x+1/3 ,, but it could also have different answers.
The missing dimension, x, is 7.5.
if you take 45 and divide it by 6 you can get the next dimension needed to get the full number, 45. You can also find it by dividing 35 and 4. I hope this helps.
Volume for rectangular prism is l x w x h
12cm x 6.5cm x 1.25cm = 97.5cm^3
