Answer:
all above
Explanation:
friction is necessary to live
Stars<span> are powered by </span>nuclear fusion<span> in their cores, mostly converting hydrogen into helium. The production of new elements via </span>nuclear<span> reactions is called nucleosynthesis. A </span>star's<span> mass determines what other type of nucleosynthesis </span>occurs<span> in its core (or during explosive changes in its life cycle). READ THIS AND YOU WILL UNDERSTAND I THINK IS TRUE </span>
Answer:

Explanation:
The equation relating the the enthalphy, pressure and temperature is expressed as

Where P is the pressure, H is the enthalphy, and T is the temperature.
since the given values are

if we insert values, we arrive at

<span>The loudness of the sound increases gradually as the air is slowly introduced in to the jar. This is because sound needs a physical medium and in a vacuum there is none. The air provides that medium and as it is introduced, the transfer of sound energy increases</span>