The following are the opening hours of the library. How many hours is it open every week? Monday Tuesday to Friday 8: 00- 17: 00 Saturday and Sunday 9
17 -8 =9:
9×4=36 (hours);
20: 00 -9: 00 = 1 1 (hour);
1 1×2=22 (hours);
36+22=58 (hours);
A: It is open for 58 hours every Monday.