If two sides of a Triangle are given the third side would be ranging between the sum and difference of

Sum of any two sides is greater than the third side.

Largest angle would be opposite to the longest side
Smallest angle would be opposite to the shortest side

180 degrees

Length x Length x Length

Length x Width x Height

There are going to be 6 faces. The surface area of a cube is 6 (L x L)

There are going to be 6 faces in a rectangular solid. The surface area would be 2 (lw + wl

Surface area refers to the amount of paint to fully cover the shape.
Volume refers to the amount of paint

There would be 2 right angles and 1 rectangle.