Answer:
temperature 3000 km below the surface of earth is varied, it's harder to know the actual temperature, it can be found around 3,000 - 3,500 degrees Celsius
Answer:
C
Explanation:
Electromagnetic waves travel at the speed of light and do not require molecules (gas, solid or liquid) to vibrate and travel.
Soundwaves when singing or from thunder vibrate particles to reach our ears and are known as mechanical waves.
Answer:
223.5 g
Explanation:
The formula between the number of moles, mass and Mr can be used to convert moles to grams.
<em>Number of moles = mass ÷ Mr</em>
So, mass = number of moles × Mr
Mr of Li₂O = (6.9 × 2) + 16 = 29.8
∴ Mass = 7.5 × 29.8 = <u>223.5 g</u>
