An emergency tire stem core remover can be made from a cotter key when both legs have been cut off to equal lengths, put a nail in the loop to creat a handle.
Concrete allways takes 125% of unmixed volume to creat a known volume due to compaction factors.
An automotive alternator will display a magnetic field when a screwdriver is dangled near the center when it is running, the front will be stronger than the back. No magnetic field mean defective.
Fill dirt takes 125% also due to 'fluffing ' dureing handleing.
Lost all the lug nuts off of a wheel? Steal one from each other wheel to limp home.
220 currant is nothing more than a pair of 110's. They can share a common nuteral/ground.
Cubic inches can be calculated on a litered engine by multiplying by .61.
Doubling a pipes size increases the flow by 300% plus the original flow.
Iron or steel boilts can be tourched out of cast iron hubs, the steel melts at about 2000 degree, the cast iron around 3600.
Concrete blocks (8 x 8 x 16) equals 1 square foot of space in a wall. Each weighs about 38 to 42 pounds.
This is just a beginning, post your knowledges here.