It's any system of geometry not based on the system in "Elements", a book from around 300 B.C.
From the Latin "to agree", it describes 2 figures that coincide when superimposed
Musical instruments are tuned to 440 cycles per second, this note on a piano
On the centigrade scale, it's the melting point of ice
1 volt times 1 amp equals this unit
Forces like gravity are measured in units abbreviated N., named for this scientist
To convert kilograms into grams, multiply by this
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