HI Any thing from two ton --two half ton depending on height and eng size
30 feet is a very unlikely size for a school!
about 30 pounds
about 5000 pounds+ water
About 30 to 40 pounds per foot, depending on body type.
20-30 tones (200000 kg
A boy that is 4 foot 9 inch should weigh between 30 to 40 kilograms. This is the ideal weight but it varies in most cases.
Pegboard panels typically weigh around 20-30 pounds per 4x8 foot panel, depending on the thickness and material used.
Depends on the size of the aquarium. Water weights 10 pounds per gallon.
Roughly 140 - 160 pounds.
Erm, I think anywhere between 130lb to 160lb is healthy...
On average, a 10-foot projector screen can weigh around 20-30 pounds depending on the material and design. It is recommended to check the specific weight provided by the manufacturer of the projector screen you are interested in to get a more accurate measurement.
The precise number will depend on the type of bindings and how tightly packed the books are. Roughly, however, one cubic foot of average books (a mixture of hard-bound and paperback), neatly (though imperfectly) packed, weighs 22 lbs.