b)since
1)Physical education
8:00(It's eight o'clock) to 8:40(It's twenty minutes to nine)
2) Literature
8:55(It's five minutes to nine) to 9:35(It's twenty five minutes to ten)
3) English
9:55 (It's five minute to ten) to 10:35(It's twenty five minutes to eleven)
4) History
10:55 (It's five minutes to eleven) to 11:35(It's twenty five minutes to twelve)
5) Geography
11:55 (It's five minutes to twelve) to 12:35(It's twenty five minutes to one)
6) Russian
12:50 (It's ten minutes to one) to 13:30 (It's half past one)
since
Объяснение: