C.
Explanation: Because mirrors are lighter, and they are easier than lenses to make perfectly smooth.
Answer with Explanation:
We are given that
Weight of an ore sample=17.5 N
Tension in the cord=11.2 N
We have to find the total volume and the density of the sample.
We know that
Tension, T=
=buoyancy force
T=Tension force
W=Weight
By using the formula
N
Where
=Volume of object
=Density of water
=Acceleration due to gravity
Substitute the values then we get
Volume of sample=
Density of sample,
Where mass of ore sample=1.79 kg
Substitute the values then, we get
Density of the sample=
Answer: Nitrogen
Explanation: Nitrogen makes up 78% of the atmosphere, Oxygen makes up 21%, and Argon 0.9%.
Water vaper makes up between 1-4%, depending on the region.
Carbon Dioxide makes up only about 0.04%.
Well over time the temperature of the water increase causeing its moleclues to move alot which causes it's state change to a gas this is who we have rain.
If you throw water on anything hot enough, the liquid water turns to steam. With this method, you can create an energy source.
