Spiders (and other small animals) are in fact fine with falls many times the height of their own body, because of the difference in how quickly volume (and therefore mass) and surface area (and therefore air resistance) are scaling. On the other hand, the larger they are, the harder they fall
Depends on the spider. When I briefly lived in AZ we had a problem with tarantulas ending up on top of our cars if we left the light on outside during the night. I knocked off off the car roof and it literally splattered. I felt bad, I assumed they would be fine.
Right in theory. But I used to live on the fifth floor and carried spiders to the window like I used to do before. In that Appartement the only difference to before was that I yeeted the spider from a height of 15m and not just 1m. That must be like skydiving without a parachute for the spider.