Answer:
Null hypothesis: the variance in hours of usage for talking is not greater than the the variance in hours of usage for internet.
: 
Alternative hypothesis: the variance in hours of usage for talking is greater than the the variance in hours of usage for internet.



Step-by-step explanation:
Let
and
be the two variables that represents the battery life in hours for talking usage and battery life in hours for internet usage respectively.
The hypothesis can be formulated as:
Null hypothesis: the variance in hours of usage for talking is not greater than the the variance in hours of usage for internet.
: 
Alternative hypothesis: the variance in hours of usage for talking is greater than the the variance in hours of usage for internet.

The standard deviation for the battery usage for talking is :

The standard deviation Is:




The standard deviation for the battery life usage for the internet is :




Thus; the standard deviation is:




Answer:
d. x2 – 2x – 4 = 0
Step-by-step explanation:
Answer:
80%
Step-by-step explanation:
Percentages are usually found by taking the value that you want to find and dividing it by the whole amount (100% of the total value available). In this case, getting 100% on the test would mean getting 120/120, because 120 points is 100% of the points available. However, the student only got 96 points out of the whole 120 points, so to find the percentage, you do 96/120 to find what part of 96 comes out of 120. Then to convert to percentage, multiply that value by 100 to get your finale value.
Answer:
Ans=0=315⁰
Step-by-step explanation:
Hope this helps :)