The two-way table of column relative frequencies below shows data on how often a teenager's parents monitor their screen time and whether or not the teenager has a time limit for their daily screen time for teenagers in West Lake County.
Frequency of monitored screen time vs. time limit for screen time

Based on the data, which of the following statements must be true for teenagers in West Lake County?
Choose 1
a. The parents of a teenager with a time limit are more likely to never monitor their screen time than the parents of a teenager with no time limit
b. A teenager whose parents occasionally monitor their screen time is more likely to have a time limit.
c. A teenager whose parents always monitor their screen time is more likely to have a time limit.
d. The parents of a teenager with a time limit are more likely to usually monitor the screen time than to always monitor it.

d.The parents of a teenager with a time limit are more likely to usually monitor the screen time than to always monitor it.

Step-by-step explanation:

The table tells us the percentages of each column (notice they add up to 1).  But it does not tell us what percent of kids have a time limit and what percent don't.  In other words, we can compare two values within the same column, but we can't compare the two columns to each other.

Options a, b, and c all compare time limit to no time limit.

Only option d compares two values in the same column.

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."