A "carat" is a system of measuring gemstones and precious metal. The word carat is thought to be derived from the word carob as the carob was used in trading. In gemstones a carat (ct.) is equal to 100 points (pts); eg a 25 point diamond is 1/4ct.
A tape mesure is used for mesuring the length or something such as, doors, windows, cloths, ect.
centimeters are used to mesure lenth, milliliters are used to mesure volume. That is like asking how many yards are in a gallon
Measuring cylinders are commonly used to measure volume, with 1cm3 being the equal to 1ml.
An ampmeter
a windsock can help you mesure air because when its blowing right you can tell the wind is blowing right
You have spelled carat correctly in your query. Carat is used as a way to measure the weight of gemstones and pearls.
A carat is a unit of weight used for gemstones. One third carat is the weight of the diamond.
Square yards
a meter stick is a device used to mesure with
Moh's scale.
Used to measure current velocities.
jewlery