as long as u can see the whole uniform, anything. on cold days if pitchers hit they usually are allowed to wear jackets. pitchers arent allowed to wear a whole lot on the field except there uniform and an undershirt. the undershirt is not allowed to be white as it is the same colour as the ball and can confuse the batter
Baseball players wear numbers so they can be easily identified on the field.
Yes, they are required to wear hats. It is a part of the required uniform for all baseball players.
They wear bowls.
nine players max.
they can if they want to i would!