Omi, didn't you mean 1/2 x 12 x 10.4 instead of 1.4 (i.e., 1/2 x base x height)
Omni is actually correct. I guess she forgot the 0 when putting in 10.4 so she put 1.4. That is why the end result isnt correct if you used 1.4. So Omni did infact have the correct answer she just forgot the 0 for 10.4.
Hope this helps ;P