D. the motion of the source or observer
The presence of helium gas indicates the radioactive sample is most likely decaying by α-decay, or alpha decay. α-decay is the type of radioactive decay in which an atomic nucleus emits α particles. α particles are Helium nuclei. So the correct answer would be α-decay.
<h3>Answer;</h3>
-Temperature
<h3><u>Explanation;</u></h3>
- Sound is a type of mechanical wave, which means it requires a material medium for transmission. It results from the vibration of particles.
- The speed of sound in mediums varies depending on the property of the medium and a number of other factors which includes; temperature, pressure, and humidity.
- Temperature increases the speed of sound wave as particles at higher temperatures tend to possess more energy and thus they will vibrate faster and thus the sound wave will travel faster.
Answer:
8.35 × 
kg
Explanation:
Remember the formula for heat:
You just need to solve for m, doing so you're left with:
Replace the variables with numbers and that's it.
