Divide the prisms into many simpler shapes (eg. rectangular cubes for volume, or rectangles/squares for surface area) so it is easier to work with and find the surface area and volume seperately. Afterwards add them together to get the final surface area or volume of each prism.
For the wedge, use:
for the volume
for the surface area of the triangular faces
I think I'll put more detail for the volume of a prism.
You need to first identify the cross section of the solid, the area which 'repeats' itself through the solid. In the first one, the cross section is a cross, in the second, it's this 'L' shape and in the last, it's a right angled triangle. Once you get their cross sectiona; area, you'll be able to find the volume by multiplying it by the depth of the solid.
The area of the cross can be obtained by dividing the cross into 5 parts; 4 rectangles and 1 central square.
Each rectangle has area 5*4 = 20.
Area of 4 rectangles = 20*4 = 80.
Area of central square = 4*4 = 16.
Total area of cross section = 16 + 80 = 96.
Volume of Prism = 96 x 3 = 288 units^3