On a day wilderness expedition you'll need to heat of water to the boiling point each day. The air temperature will average . You have available canisters of compressed butane fuel, which you'll burn to heat the water. Each canister has of butane in it. What is the minimum number of fuel canisters you must bring? The standard heat of formation of butane at is . You'll probably find other helpful data in the ALEKS Data resource.

small = small current large mag large current

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia