mtm nkjrki uriue iidj jek jfdfk sj dh jgb banna
millimetres (centimetres could also be used)
None of them. I would use litres. However, if you wish to use non-standard, obsolete units you could use "gallon".
You would use the metric unit "liters" to measure the capacity of a hot water tank.
This question cannot be answered sensibly. A gallon is a measure of volume, with dimensions [L3]. A pound is a measure of mass, with dimensions [M]. Basic dimensional analysis teaches that you cannot convert between measures with different dimensions such as these without additional information. It takes only a little mental effort to compare a gallon of air and a gallon of treacle to see that the two will have very different masses.
A stopwatch or a timer would be suitable to measure the time it takes to bring water to a boil.
millimetres (centimetres could also be used)
Liters.
Which unit would you use to measure the water in a full tub?
Gallons
the answer is quarts
This depends on the country yo live in. Some countries measure it in gallon and some in liters. 1 gallon = 3 liters.
I wiil use water
pounds
.
Litre and gallon
You can certainly use any "metric" graduated cylinder or such and convert to gallons. The problem is that few scientific instruments are made in gallons, and most household items aren't celebrated. Probably the best thing would be a pyrex measuring pitcher. Another thing you could do is to take a gallon milk jug, or a bucket. Tare it on a scale. Then measure out an amount of water equal to 8 pounds and mark it. You now have a custom gallon measuring jug.
There are 4 quarts in 1 gallon. So you would need 4 quarts of water to fill a gallon.