It is on Sunday,September 23 @1:10 P.M .
A=-112 bcs -216 ft is down from sea level and -104 is also down from sea level bcs both values are in minus but -104 is higher than other so you can minus it from -216 the difference is the answer
b=-109
Time taken to drive to her grandparents house = 6 5/6 hours
We convert this mixed into improper fraction, we get = 41/6 hours
Time taken to drive to her grandparents house = 41/6 hours
Time taken to drive back = 8 2/9 hours
We convert this mixed into improper fraction, we get = 74/9 hours
Time taken to drive back = 74/9 hours
Difference between the two = 74/9 - 41/6 = (148-123)/18 = 25/18 hours = 1 7/18 hours
Therefore it took 1 7/18 hours longer to drive back.