Final answer:
The unit for the number 72 cannot be stated. Units give meaning to numbers in measurements and are essential for understanding what is being measured. Conversion factors are used to convert and simplify units during calculations.
Step-by-step explanation:
To answer the question, we need to know the context of the 'dotted line' referred to, which is not provided here. Without additional context, it is not possible to accurately state the unit for 72. However, in general, the unit for a number depends on what is being measured. For example:
Volume: the number 32 might have a unit of fluid ounces.
Temperature: the number 98.6 would typically be in degrees Fahrenheit.
Speed: 88 could be meters per second.
Units are important as they give meaning to the numbers we use in measurements. Without the proper unit, a number can be meaningless since it doesn't convey what is actually being measured or the scale being used.
In math problems that involve units, the units often need to be converted using conversion factors to make sure that they match and can be properly compared or combined. For instance, when multiplying or dividing quantities with units, like in unit conversion, the units also get multiplied or divided, and may then be simplified or converted into other relevant units.