To calculate the distance between two points, we can use a formula that is a variation Pythagorean Theorem. Look:

"d" represents the distance and coordinates are expressed as follows: (x, y)
Let's go to the calculations.

The answer is 6.7 uc.
Answer
no number from the following list can be expressed as the sum of three squares: 7, 15, 23, 31, 39, 47, ect... so only once
Step-by-step explanation:
nono dont touch me there this is my nono square
I hope I answer your question
The polygon in option 3 is not octagon at all, it is heptagon (or 7-sided polygon).
A convex octagon has no angles pointing inwards. More precisely, no internal angles can be more than 180°.
When some internal angle is greater than 180°, it is concave.
In option 2 you can see that one angle is pointing inward, then this octagon is concave.
Answer: correct choice is B.