Here is what to do first find the are of the bigger rectangular prism, 5*5*9=225 in^{3}

After that, find the height of the triangular prism, 8-5=3

then find the volume of the triangular prism, ((3*4)/2)*5=30

Add those volumes together, 225+30=255 in^{3}

255 in^{3}

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