Answer:
The 99% confidence interval for the fraction of U.S. adult Twitter users who get some news on Twitter is between 49.34% and 60.66%, which means that we are 99% sure that the true percentage of US adult Twitter users who get some news is in this interval.
Step-by-step explanation:
Confidence interval:
A confidence interval has the following format:

In which M is the sample mean, z is related to the confidence level and s is the standard error.
55% of U.S. adult Twitter users get at least some news on Twitter (Pew, 2013). The standard error for this estimate was 2.2%.
This means that 
99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Lower bound of the interval:
Upper bound:
The 99% confidence interval for the fraction of U.S. adult Twitter users who get some news on Twitter is between 49.34% and 60.66%, which means that we are 99% sure that the true percentage of US adult Twitter users who get some news is in this interval.
Answer:
The zero of the function is; (-4,0). The y-intercept is; (0,4). The horizontal asymptote is; y =2. The vertical asymptote is; x= -2
Step-by-step explanation:
The zero of a function is the point where the graph of the function crosses the x-axis. The y-intercept is where the graph of the function crosses the y-axis. The horizontal asymptote is a horizontal line that the function approaches but never touches or crosses it. Finally, the vertical asymptote is a vertical line that the function approaches but never touches or crosses it
This is a problem in direct variation. For every five minutes that goes by, Liz utters 225 words. The general form of an equation of direct variation is
w = k x, where w is the # of words, k is the constant of proportionality and x is the number of minutes that have elapsed.
Find k by dividing 225 words by 5 minutes, to find the number of words per minute.
Next: How many minutes are there between 10:30 a.m. and 11:15 a.m.? Calculate w=kx, using your constant of proportionality, k, and that number of minutes.
M = (y2-y1)/(x2-x1), so the answer would be -2/3