What is the surface area of a regular pentagonal prism with side length 8, altitue 20 and apothem approximately 5.5

The surface area of the pentagonal prism is given by:
SA=2[area of the pentagonal sides]+5[area of rectangle sides]
Area of pentagonal side will be given  by:
Area=5/2 sa
where;
side,s=8
apothem ,a=5.5
hence;
Area=5/2*8*5.5=110 sq units

Area of rectangular side will be:
Area=length*width
=20*8=160 sq units
therefore the surface area (SA) will be:
SA=110*2+5*160
=1,020 sq. units

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