Questions

As the frequency of sound is higher, women have shriller voices than men.

The shrillness or pitch of a sound is determined by its frequency. The higher the pitch shriller the voice. As the sounds produced by vocal cords of women are higher than men so women have shriller voices than men. Because their vocal cord is of smaller size. As their vocal cord is more stretched than men's.

Vitamin K helps in clotting of blood. It is used by the body to help blood clot.

Warfarin (Coumadin) is used to slow blood clotting. By helping the blood clot, vitamin K might decrease the effectiveness of warfarin (Coumadin).

Given that man's father is my father's son => Me because i have no brothers

=> Mans father is me.

Hence, that man is my Son.

The key to this math riddle is realizing that the one place must be zero.
888 +88 +8 +8 +8 =1,000