It is a function because every Celsius temperature is associated with only one Fahrenheit temperature. Therefore, option B is true.
We are given that the temperature in degrees Celsius C can be converted to degrees Fahrenheit F
We know that the formula
[tex]\dfrac{C}{5} = \dfrac{F - 32}{9}[/tex]
If we are substituting c = -40
Then, we get
[tex]\dfrac{C}{5} = \dfrac{F - 32}{9}\\\\\dfrac{-40}{5} = \dfrac{F - 32}{9}\\\\-8 \times 9 = F - 32\\\\F = -72 + 32\\\\F = -40[/tex]
For every Celsius temperature, we get only one value of Fahrenheit.
The function is one-one because for every value of Celsius we get a unique value of Fahrenheit.
Hence, it is a function because every Celsius temperature is associated with only one Fahrenheit temperature.
Therefore, option B is true.
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