Number of electron determine reactivity
<span>This theory was suggested around 450 BC</span>
Answer: A
Explanation: A, because when you eat it is you use chemical energy afterward you run and use mechanical energy. Ex of Chemical energy can be batteries and you digesting food. Mechanical is movement.
<span>(2) butynu........................</span>
9,000 meters
Because density is altered by altitude, the helium balloon can reach a height of 9,000 meters, or 29,537 feet. Anything higher than this altitude will cause the helium within the balloon to expand and the balloon to pop.
