Nirvana
Because otherwise they'd be lizards.
Three swallows!
A light bulb weighs about 50g and a single ant can lift about.2g, so it takes somewhere around 250 ants working together.
The mathematician says "2" The Physicist says "2, plus or minus 0.1" The engineer says "Probably around 2, but let's say 3 to be on the safe side".
All Apologies
The finish line at the Boston Marathon.