Answer:
28 1/2 hours
Explanation:
The first weekend she worked:
Fri: 4.5 hours
Sat: 5.75 hours
Sun: 4 hours
So the total of those = 4.5 + 5.75 + 4 = 14.25 hours.
Then she worked the same thing again the next weekend.
So:
14.25 x 2 = 28.5 which is 28 1/2 hours