1. A new company came out with a new battery that promised that it would last for more than 8 hours with the standard deviation of 1 hour. A group of researchers studied these batteries. They tested 100 batteries and discovered that they lasted about 8.5 hours. Is company's claim about the new battery supported at the 1% level of significance (?)?
A. Yes
B. No
C. Cannot answer with this information
2. A counselor claims that 20% of all students who take SAT score at least 1200, 25% score between 1000 and 1190, and the remaining 55% score below 1000. A sample of 120 students showed that 20 students had the score of 1200, 35 had a score between 1000 and 1190, while the remaining 65 students scored below 1000. Test the counselor's claim at 0.05 level of significance, using p-value of 50%.
A. Counselor has a valid claim
B. Counselor has invalid claim
C. Cannot aswer with this information
3. A data set consists of the values 2, 6, 3, and 1. If we consider this a population (all the values available), the variance is
A. 12
B. 14
C. square root of 3.5
D. square root of 15
E. none of these
4. The best method of presenting data that occurs over a period of time is:
A. Bar chart
B. PIe chart
C. Line chart
D. All of these are equally effective