<h3>
Answer: 
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n starts at 1, and n is a positive whole number (1,2,3,...)
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Explanation:
The sequence is arithmetic with first term 40 and common difference 10. Meaning we add 10 to each term to get the next one.
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a1 = 40 = first term
d = 10 = common difference

is the general nth term of this arithmetic sequence
Plug in n = 1 and you should get 
Plug in n = 2 and you should get 
and so on
The answer is 112.09 i added 89+3+3+8+2=105+7.09=112.09
I believe the answer is, 2) End of Reconstruction
the coordinates where the bridges must be built is
and
.
<u>Step-by-step explanation:</u>
Here we have , a road follows the shape of a parabola f(x)=3x2– 24x + 39. A road that follows the function g(x) = 3x – 15 must cross the stream at point A and then again at point B. Bridges must be built at those points.We need to find Identify the coordinates where the bridges must be built. Let's find out:
Basically we need to find values of x for which f(x) = g(x) :
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
Value of g(x) at x = 3 : y=3x -15 = 3(3)-15 = -6
Value of g(x) at x = 6 : y=3x -15 = 3(6)-15 = 3
Therefore , the coordinates where the bridges must be built is
and
.