The two trianglular faces we see have area
(1/2)(18)(14.1) and (1/2)(10)(16)
There's two more like these we can't see.
And the base has area
(18)(10)
for a total area of
A = (18)(10) + 2 ( (1/2)(18)(14.1) + (1/2)(10)(16))
A = 593.8
Answer: second choice
