after a bit of cod 4 nostalgia:
barrels of crude oil will immediately explode upon shooting, but a propane cylinder is bulletproof
helicopters can take several direct hits with rifle grenades and don't consider leaving the area
if you run fast enough towards a tank, you'll be fine
shotguns have a maximum effective range of 10 feet
if i carry a rifle and a pistol, i can carry only 420 rounds of rifle ammunition, but if i carry 2 rifles i can carry twice as much ammo without encumberment
the fabric covering on the back of trucks is bulletproof
you can easily pick up and throw back grenades