How can i find the volume of each figure

The volume of any rectangle is 

length x width x height  = cubic units

Convert fractions to decimals (easier to multiply with) and solve 

Label the units as: cubic feet, cubic inches, etc

1) 6 x 3.33 x 1.66        2) 2.25 x  3 x 2.25   3) 15 x ? x ? 

4) 10 x 3.5 x 1.5           5) 4 x 1.75 x 2.5     6) 5.25 x 3.75 x 2

Hope this helps. 

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)