Zhukov, now a lieutenant-general, is assigned to the First Soviet Mongolian Army Group in July. After being given command of the group he prepares to take on the Japanese. The conflict climaxes at the Battle of Khalkin-Gol, beginning on 20 August.
If you have a normal 28 day cycle, you are most likely to become pregnant when you have unprotected intercourse approximately 2 weeks before you anticipate your period to start.
This means that this gal can get pregnant by having unprotected sex starting 7 days before ovulation date (or on the 7th day after menstruation started, in this case it's the same), and about a day after. Just so we're clear, this means from day 7 to day 15. We have no clue as to how long your cycle is.