No.
Yes, but if I were you, I wouldn't try it. Though you can if you want.
No, if there is a runner on first and the second baseman fields the ball and throws it to the shortstop, who muffs the play and allows both the runner and batter to advance/reach safely, the play would be ruled a fielder's choice and an error. It would still count as an at-bat and a non-hit for the batter, just as if the second-baseman had muffed the throw to the first-baseman with nobody on base.
Yes. For example, runner on 2nd, batter hits ground ball to the shortstop, who, instead of throwing to first, throws to third base in an attempt to get the runner. The batter is charged with reaching first on a fielder's choice, even if the runner is safe or out.
The runner is probably out for interference by running into a fielder, if not, he is out if the throw to first beat the runner and the first baseman, or whom ever is covering first, had his foot on the bag when he received the ball.
This is ruled a Fielder's Choice (FC) in the scorebook. The batter is charged an at-bat, with no hit issued.
It's a play where in the fielder throws the ball to 1st base to get the batter-runner out. This play is always done when there are no runners on base.
That would be considered a fielder's choice. Answers.com defines a fielder's choice as: "A play made on a ground ball in which the fielder chooses to put out an advancing base runner, thus allowing the batter to reach first base safely." Even though, in your question, the runner was not put out at home the play would be scored a fielder's choice and the batter would be credited with an RBI.
The run would not count since there are 2 outs and the fielder got the out at 1st base which is the only thing that matters in that situation with 2 outs regardless of the runners and regardless of any of the other circumstances of who is on base.
Once the batter/runner is forced out at 1st base, the force out of all other base runners is no longer in effect. Therefore, even if the original runner at 1st falls, he must be tagged out. He could, in fact, return to first and be safe there if he is not tagged out.
"A" is the abbreviation for an "Assist", a scoring record of a fielder who throws out a runner, such as a ground ball to short and the batter is thrown out at first, the shortstop is credited with an Assist. Two "Assist" may sometimes be credited, such as when the ball is hit to the outfield, the outfielder may throw to another fielder who then throws the baserunner out. In that case both players involved in throwing out the runner is credited with an "Assist".
To prevent collisions between runner and fielder
The fielder has to have the ball in his possession but if he drops it he doesn't have to tag up. Actually, the fielder doe NOT have to have possession of the ball for a base runner to tag up and advance. Once the runner is on the base ("tagging up") he may advance as soon as the fielder touches the ball, whether he has possession or not. In other words, the base runner may advance even if the fielder is bobbling the ball and then catches it, i. e. has possession.