You don't. Liters is a unit of volume, atmospheres is a unit of pressure.
To convert liters to fluid ounces: liters x 33.81 = fluid ounces
Liters IS volume - there is nothing to convert.
atmospheres
To convert cubic meters to liters, you multiply by 1000.
Multiply psi x 0.07 to get atmospheres.
mmHg x 0.001316 = atmospheres749 mmHg x 0.001316 = about 0.9855 atm
First convert quart into liters (multiply by 1.1365), then convert liters into milliters (multiply by 568.26)
A hectoliter is equal to 100 liters so 42.9 hectoliters would convert to 4290 liters.
hl means hectoliter, or hundreds of liters, so you simply multiply by 100 to convert to liters.
You cannot convert a volume to an area. You can, however, convert liters to cubic meters, since both are volumes. There are 1000 liters in a cubic meter, so to convert to cubic meters divide by 1000 liters / cubic meter.
Multiply inches of mercury by 0.033421057 to get atmospheres.
Convert everything to the same unit, then add. (Either divide milliliters by 1000 to convert to liters, or multiply liters by 1000, to convert to milliliters.)