The section “chemical change or physical change” includes words and phrases such as “sometimes it is difficult” and “remember” How do these words and phrases contribute to the tone of the article?

Design techniques and materials that reduce the negative environmental impact of a structure are referred to as

The fact that the total amount of energy in a system remains constant is a(n)

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