The surface area is ≈ 451.92
The sum of an Arithmetic Series is given as:

where,
d = Common Difference = Difference of any two consecutive terms.
So,
d = 8
a1 = First term = 1
Using the values, we get:

The above equation gives the formula for n terms of an Arithmetic Series.
So, option A is the correct answer
It’s a straight line increasing
Does that answer your question?
Answer:
5
Step-by-step explanation:
Divide 30 by 6, since this will find the number of chairs she can paint in 1 minute:
30/6
= 5
So, the constant of proportionality is 5, since she can paint 5 chairs in a minute.