Do the Math

The troofers are all excited that they are going forward with their "truth burn" project at the Burning Man festival. I was rather amused by this description:

The sculpture will be destroyed by about 40 lbs of remotely ignited thermite towards the end of the festival.

OK, think about this for a minute. If it takes them 40 lbs of thermite to destroy a 20 foot tall sculpture, how much thermite would it take to destroy two 110 story skyscrapers?