Answer:Think of the equation as an equation for a line
y=mx+b
where in this case
C= 5 /9 (F−32)
or
C= 5 /9 F - 5/9 x 32
You can see the slope of the graph is 5 /9
, which means that for an increase of 1 degree Fahrenheit, the increase is
5 /9 of 1 degree Celsius.
C= 5 /9 (F)
C= 5/9(1)
C=5/9
Therefore, statement I is true. This is the equivalent to saying that an increase of 1 degree Celsius is equal to an increase of
9/5 degrees Fahrenheit.
C= 5/ 9 (F)
1= 5 /9 (F)
(F)= 9 /5
Since
9/5 = 1.8, statement II is true.
The only answer that has both statement I and statement II as true is D, but if you have time and want to be absolutely thorough, you can also check to see if statement III (an increase of 5/9 degree Fahrenheit is equal to a temperature increase of 1 degree Celsius) is true:
C= 5 /9 (F)
C= 5 /9 x 5/9
C=25/81
(which is≠1)
An increase of 5/9
degree Fahrenheit leads to an increase of
25/81.
, not 1 degree, Celsius, and so Statement III is not true.
The final answer is D.
