A machine P can print one lakh books in 8 hours, machine Q can print the same number of books in 10 hours while machine R can print them in 12 hours. All the machines are started at 9 a.m. while machine P is closed at 11 a.m. and the remaining two machines complete the work. Approximately at what time will the work be fnished? 1. 11:30 a.m. 2. 12 noon 3. 12:30 p.m. 4. 1 p.m. 5. 2 .m.