Answer:
Well
If we choose plan B then it would be better. 15 cents a messages would be 3 messages in total if we choose plan b.
Step-by-step explanation:
We have the formula

From the above formula,

That is variance of Y is 49 not 7.
Hence the statement is (b) False
F=9/5C+32
-9/5C+F=32
-9/5C=-F+32
C=9/5F-57.6