We use "=" signs below, but all are approximate.
:'''100 __C''' ? '''''212 __F''''' ? water boils :'''37 __C''' ? '''''98.6 __F''''' ? human body temperature :'''0 __C''' ? '''''32 __F''''' ? water freezes :'''-18 __C''' ? '''''0 __F''''' ? ouch :'''-40 __C''' ? '''''-40 __F''''' ? ''forty below zero!''
'''Humidity.''' Hot weather, say 80__F (26__C) and up, is more uncomfortable in '''humid''' air than in dry air because dry air allows more sweat to evaporate from your skin and this cools you but humid air inhibits this evaporation and leaves you more susceptible to overheating.
For those who are not used to Metric thermometers, there are a few ways to think about it...
'''Option 1''': From Metric (Celsius) to Fahrenheit, double the number and add 30. From Fahrenheit to Celsius, subtract 30 and divide in half. This is not exact and it won't work for much higher or lower temps, but it will be close enough to understand what the temperature is.
'''Option 2''': A nice little poem to remember for Celsius... Zero is freezing 10 is not 20 is warm and 30 is hot
'''Option 3''': For the mathematically inclined: Fahrenheit=(C*1.8)+32. Celsius=(F-32)/1.8
For China, the jing is almost exactly 500 grams.
For floor area of an apartment, there are about 11 square feet to the square meter.
For large areas, there are about 2.5 acres to the hectare.
The standard metric unit of volume is the litre. Many things, however, are measured in ml (millilitres) or equivalently in cc (cubic centimetres). Roughly, a teaspoon is 5 cc and a fluid ounce is 30 cc.
In both the US and Imperial systems, 4 quarts = 1 gallon and 2 pints = 1 quart. However, the US units are smaller than Imperial counterparts. A US quart is 32 fuid ounces while Imperial is 40; a liter is in between at 35. A US gallon is 128 ounces or 3.78 litres, while an Imperial gallon is 160 ounces or 4.54 litres.
For car and motorcycle engines, displacement might be given in cc or litres or cubic inches. 1000 cc or one litre is 61 cubic inches.
1 mm = 1 / 1000 metres, 1 mg = 1 / 1000 g, 1 mL = 1 / 1000 Litres.
1 cm = 1 / 100 metres.
1 km = 1000 metres, 1 kg = 1000 grams.