Hmmm im reallt not sure this pretty hard im stuck i need help!
The three changes of state during which energy is absorbed are:
1. Change from solid to liquid - Melting.
2. Change from liquid to gas - Vaporization
3. Change from solid to gas - Sublimation
All these changes of state require heat energy to break the attractive forces that hold the particles of the molecules together, so that they can move into more disorderly states. For instance, when heat is applied to a solid, the solid absorbs the heat and use it to break the attractive forces that are holding the molecules of the solid together. At a particular temperature, the attractive forces will be completely overcome and the solid framework will collapse, thus leading to the melting of the solid.
Answer:
Rate of change of volume of the pile 
Explanation:
Given -
Rate of increase of the base of the pile
inches per minute
Height of the pile
the radius of the base
Let "h" be the height of the pile and "r" be the radius of the base.
Then 
Radius "r"
inches
Rate of change of radius i.e

Volume of conical pile

Change in volume of conical pile

Substituting the value of rate of change of radius, we get -

Rate of change of volume of the pile 
Answer:
Stephen Stearns states that natural selection doesn't mean the survival of the fittest organisms, but rather this mechanism is illustrated by the selective reproduction of the fittest. Natural selection can be classified into distinct types, including directional, disruptive and stabilizing selection, which are in turn based on sexual selection. These types of selection are driven by different outcomes that have different dynamics.
1. courtship rituals 2. attract a mate 3. internal fertalisation occurs inside the feamales body whereas external fertalisation occurs outside the feamales body 4. <span>Gametes may get washed away 5. the devoloping zygote is protected</span>