Answer:
"Teens and Distracted Driving: Texting, Talking and Other Uses of the Cell Phone Behind the Wheel"
a. The inference made involves estimation. The question provided that the statements were made on the basis of the resulting data and not on the basis of some hypothesis testing.
This implies that some statistics were calculated from sample data to approximate the population parameter, as shown in the statements. The statements were not an attempt to establish the statistical significance of some claims.
b. The population of interest is American teenagers between 12-17.
Step-by-step explanation:
An inference from data is a statistical estimation by which some statistics are calculated based on the sample data of 800 teens between the ages of 12 and 17. The statistics serve as an approximation to the population parameter.
Inference based on hypothesis testing establishes if a claim has statistical significance by providing statistical evidence in favor of the claim or against it.
Answer: 
<u>Remove "x" and add</u>
-2 + 9 = 7
<u>Add "x" back</u>
7 -----> 7x
Note: When adding/subtracting problems like these remove "x" and then add/subtract normaly. When you get your answer put x back.
