Answer: 1093.5
Step-by-step explanation:
The area of the bottom and top faces are each (26)(7.5)=195, so their combined area is 195(2)=390.
The area of each of the rectangular faces lying on the 7.5-inch side is (7.5)(10.5)=78.75, so their combined area is (78.75)(2)=157.5.
The area of each of the rectangular faces lying on the 26-inch side is (26)(10.5)=273, so their combined area is 546.
So, the total surface area is 546+157.5+390=1093.5
