What is the easiest way to measure.

Step-by-step explanation:

So, we can assume that LN and PO are equal in length and NO and LP are equal in length as well.  LO and PN are also equal.

We can see that PN is the hypotenus of either triangle NLP or NOP.  LO is the hypotenuse of LOP and LON, so those could be used to find the length as well.  I rather work with NOP, but any work.

We know that NO is 8 units long and LN is 6 units long.  Because LN = PO, PO = 6 units.

So, using the pythagorean theorem, the hypotenuse is:

8^2 + 6^2 = c^2

64 + 32 =c^2

sqrt(96)=c

c~9.8

I don't know how exact they want your answer.

c = 9.79795897113