31% of 40 is 12.4 exactly
Answer: 0.82 miles per gallon
Step-by-step explanation:
Given : Jenna has bought a new hybrid car. Each week for a period of seven weeks, she has noted the fuel efficiency (x) (in miles per gallon) of her car.
The results are :45 44 43 44 45 44 43
The formula to find the standard deviation is given by :-

First we find mean of the given data ,

Now,


Now, standard deviation of the above results will be :-

Hence, the standard deviation of these results = 0.82 miles per gallon
Answer
intersecting lines
Step-by-step explanation:
The second option is the answer