Expo dry-erase markers are typically considered some of the best in the industry for their clarity and lifespan. A major competitor named Whypo claims that their markers last longer on average than Expo markers and they attempt to show this fact by using a random group of 15 Whypo markers. Whypo finds that their markers have a mean lifespan of 32 days, with a standard deviation of 8 days. Typically, an Expo marker under daily use will have a lifespan of 20 days before needing to be replaced

Check the conditions for Whypo's Hypothesis

y=mx+b

step-by-step explanation:

m is slope, b is y-intercept

the height of the surface increases from the center out to the sides of the road.

step-by-step explanation:

as we move out we move away from the x-axis.

and as mentioned in the problem statement that height of a road increases when we move away from the center x.

hence proved that 3rd option

the height of the surface increases from the center out to the sides of the road.

is the correct option.

there are no choices to this, can you give us some choices so that i can answer it

step-by-step explanation: