Every day, 500 airplanes in san francisco incur an additional 30 minutes of airport delays when flying into or out of the airport. in chicago, the delays amount to 15 minutes for 1,400 airplanes. if the price of time is $20/hour in san francisco and $15/hour in chicago, which airport incurs the largest opportunity cost?

you can lose ranking 2 ways.

1) you don't have enough points due to you expending them by asking questions/your answers are deleted.

2) your brainliest's expired. this means that brainliests, once they exceed the 30 day limit, expires. this is to ensure that you continue to contribute into the community at a constant rank if you want to continue to have/exceed the rank you have right now.

if you go to profile, and click "show more information" located on the bottom left of the box with your information (on top of the questions answered, questions asked, and friends), you will be given the following information (example):

member since : 02/13/2017, 18: 11

questions answered: 9741

questions asked: 162

no. of brainliest answers: 1575

brainliest answers in last 30 days: 10

warnings: 0 view

questions/answers reported: 2637

questions/answers incorrectly reported: 64

look at the "brainliest answers in the last 30 days". this is the one that will affect your rank other than your points. again, once your brainliest expires (was earned 31+ days ago), it will not be counted.

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