A1 would be the first y value, which is 3 and d is the ratio ( distance between each y value) which is 3 ( add 3 to the y value to get the next one)
The answer is a1= 2, d = 3
Step-by-step explanation:
13+5+5+4.3
<span>
<u><em>The correct answer is:</em></u>16%.
<u><em>Explanation</em></u><span>
<u><em>: </em></u>We use a z-score to answer this question.
<u>The formula for a z-score is:</u>
z=</span></span>

<span><span>,
where mue is the mean and sigma is the standard deviation.
<u>Using our information, we have:</u>
z=</span></span>

<span><span>.
Using a z-table, we see that the area to the left of, or less than, this score is 0.8413. We want to know how many students scored more than this, so we subtract from 1:
1-0.8413=0.1587, which rounds to 16%.</span></span>
I think it’s A or D not sure. Hope I helped.