Answer:
~~Now, you have left your question very open ended and didn't ask for any particular kind of answer so I'll do my best to get what you're looking for.~~
A physical change in a substance doesn't change what the substance is. It can possibly melt or freeze an object. I mean heat makes things expand while cooling makes them retract.... In chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
Jet stream<span>ˈjet ˈˌstrēm/</span>noun1.a narrow, variable band of very strong, predominantly westerly air currents encircling the globe several miles above the earth. There are typically two or three jet streams in each of the northern and southern hemispheres.
(credit to google)
Given that,
Energy 
Surface temperature = 11000 K
Emissivity e =1
(a). We need to calculate the radius of the star
Using formula of energy



Put the value into the formula


(b). Given that,
Radiates energy 
Temperature T = 10000 K
We need to calculate the radius of the star
Using formula of radius

Put the value into the formula


Hence, (a). The radius of the star is 
(b). The radius of the star is 
Answer:
v= 4055.08m/s
Explanation:
This is a problem that must be addressed through the laws of classical mechanics that concern Potential Gravitational Energy.
We know for definition that,

We must find the highest point and the lowest point to identify the change in energy, so
Point a)
The problem tells us that an object is dropped at a distance of h = 1.15134R over the earth.
That is to say that the energy of that object is equal to,


Point B )
We now use the average radius distance from the earth.


Then,


By the law of conservation of energy we know that,

clearing v,



Therefore the speed of the object when it strikes the Earth’s surface is 4055.08m/s
D, it depends. For water, the solubility increases as it get hotter, up to 100 degrees, but in some cases, liquids behave the opposite way.