Answer:
A. -6
Step-by-step explanation:

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∴ 
The equation of the line of best fit of a scatter plot is y = -8x + 3.
This equation is in slope-intercept form, or y = mx + b, where m is the slope and b is the y intercept.
Thus, the y intercept in this equation is 3.
As 7 is above 5 so we round up 4 to 5. So the answer is 500 bcos the place where the number 4 is, is the hundredth place.