In the given inequality a=10, so the solution of the given inequlity are
x<-10 and x>10.
It means all the numbers less than -10 and more than 10 are in the solution set. We have open circle at 10 and -10 because 10 and -10 are not included in the solution set.
Well first you need to find the unit rate. Divide 15 by 3.....get 5 minutes for 1 mile. Then you would multiply 5 by 8 which is 40 so 40 minutes (B) is your answer :)