SOMEONE JUST ANSWER THESE ALREADYILL MARK BRAINLIEST TO THE BRAINLIER! Which correlation is most likely a causation?

the positive correlation between the number of skiers and number of snowboarders on a mountain
the positive correlation between the sales of cell phones and the sales of televisions in a store
the positive correlation between the number of typing classes a student takes and the number of words per minute the student can type
the positive correlation between the number of shopping carts at a store and the number of cash registers in the store
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2.What is the linear function equation that best fits the data set? (GRAPH BELOW)
yˆ=x+2
yˆ=2x+1
yˆ=2x−1
yˆ=x+1
3.
The equation of the linear regression line represents the relationship between the amount a person earns, x, and the amount saved, y.

yˆ=0.01x+50

What does the slope of the line represent?

For every $100 a person earns, the savings increases by 1 cent.
For every $100 a person earns, the savings increases by $1.
For every $100 that a person earns, the savings decreases by $1.
For every $1 a person earns, the savings increases by $100.