remember that to put a number in scientific notation is necessary to have the first digit of the number different to 0, so

to calculate the order of magnitude, if the number is greater than 3.16, we assume it as a 10, so in this case as 7.654 > 3.16 we get that the order is

So the order is 10^-3
I think the answer is 5 feet because 2(2+5)= 4+10=14. So the missing length is 5 feet.
What you have here is the fibonacci sequence.
Each number in the sequence adds itself to the number before it.
1+1 = 2
1+2 = 3
3+2 = 5
5+3 = 8
8+5 = 13
the sequence is 0,1,1,2,3,5,8,13
So as you can see, -3 is the y-intercept. You would make a point on (-3,0) first. Then from the point, you would go up 1 and go right 2 because the slope is a positive 1/2 slope.