Will give brainliest what are the 5 basic rules of softball? what is softball?

Some rules are:
-A team must have 9 players to start,
-Bats must be official softball bats(no metal screws or screw-in cleats are allowed)

Field, Players, and Equipment
The Field - The baselines will be 65 feet. The distance from pitcher's mound to home plate will be 50 feet.
The Players - A team must have 9 players to start or to continue a game with the maximum of 10 players (not including an EP - SEE LAST RULE UNDER BATTING).
Substitutes - A player is officially in the game when his/her name has been entered on the official score sheet. Once a player leaves the line-up, he/she may re-enter the game. FREE SUBSTITUTION/All teams must turn in batting order. No pinch runners...only in case of injury and that player cannot return to the game.
The captain is the only player who may address the officials during the game, but only on matters of rules interpretation.
Equipment - No metal screws or screw-in cleats are allowed. Rings, earrings, necklaces, and bracelets are advised not to be worn. Bats must be official softball bats.
Add-ons must be made to a roster prior to the SECOND game of Intramural softball season.

Letter d i believe letter d

Sodium is the answer