Answer:
c
Step-by-step explanation:
i know it c
Answer:
is sometimes positive and sometimes negative.
Step-by-step explanation:

Take 

Take 

Hence
for
and
for 
So
is sometimes positive and sometimes negative in the interval.
Answer:
11
Step-by-step explanation:
-15, -15, 7, 8, 11, 16, 17, 18, 18
find the middle number after numbers are in order
hope this helps :)
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