Answer this please ty

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude

Avolleyball player hit a ball with a mass of 0.25 kg. the average acceleration of the ball is 15.5 m/s². how much force did the volleyball player apply to the ball? 62.0 n 3.87 n 62.0 m/s² 3.87 m/s²