Answer:
6 kilometers
Step-by-step explanation:
It's a right there answer. I really don't understand what yoy are asking...
In this case, the complement would be selecting a number less than or equal to 7; the probability of this occurring is 
I believe it would look like this
---------E --------M
/
S/----------M----------E
/
/
/ -----------S--------------M
/ /
/ /
/---------E /
\ \
\ ----------------M-------------S
\
\
\ /-------------------M-------------S
\ /
M/
\
\----------------------S------------E