Step-by-step explanation:
the set builder form for [6,7,8,9, ....] is given as:

Answer:
I think -3.5 is the right answer
Mr Wellborn arrives at work at 7:50 am. If you take 60 minutes away from 8:40 its 7:40 but take away 10 minutes and its 7:50.
wow the answer is not listed on option