This is as far as i got can you check my work so far and tell me where to go from here

Which addition property is being illustrated below? (type commutative or associative) (6 + 7) + 1 = 6 + (7 + 1)

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%

Ascatter plot with a trend line is shown below. which equation best represents the given data? y = x + 2 y = x + 5 y = 2x + 5