The base of a rectangular solid is a square with a side of the length a cm. the height of the rectangular solid is b cm and its volume is equal to vcm³. express the variable a in terms of b and v.

Volume of a rectangular solid is given by length ×width ×height or the base area × height.
In this case the base is a square hence the base area = a cm ×a cm = a² cm²
therefore, the volume will be a² cm² ×b cm = a²b cm³
hence, a²b cm³ = V cm³
           dividing both side by b , a² = V/b , then we get the square root
          therefore, a = √(V/b)
                                                  

Well let’s see here we need nuts and more nuts and probably more nuts so why not‍♂️

The answer to your question is the last one