Traveller returned home in Ramadhaan during the day and wants to have sexual intercourse with wife

A man returned home from a journey and had not been fasting [due to his travels, so he] decided [now he was at home] to fast [the rest of the remaining day]. He then found his wife taking a bath [since she had] completed her menses; Is it permissible for him to have sexual intercourse with her in this case or should they both assume the fast for the [remainder of the] day?

Fasted the whole day and saw three drops of menses blood

Does the passing of wind (flatulence) from a male and female necessitate washing the affected area with water? And what is required of the woman from whom three drops of blood came out at the expected time of the onset of her menses whilst she is fasting and then stopped?