Maybe two-thirds of the schools. Sometimes it is possible to attend two schools even if the scores are the same and the volunteers are the same. After all, the investment line is unknown, so your's performance must be similar.

Better not be bad. If someone is willing to sacrifice their scores, they can report according to the wishes of those with lower scores. The gap within 20 minutes should not be a big problem.

If you want to go to the same school, there are usually high and low. Generally, the score is within 20 points, that is, people with high scores must be accommodated by about 20 points. If you have to be in a school, you can set up a school with 100% admission and a low score. Those with high scores will definitely participate, and those with low scores can be admitted, but it is not recommended.