Answer: Yes, Natural selection is natures way of making the fittest and top dogs of the food chain, It can produce a change in individuals and populations by completely reducing or wiping out a population not fit for survival in its inviroment and can even force a change of the creature to make it able to survive.
Example: would be rabbits, a snow rabbit wouldn't survive very well in the desert and a jack rabbit wouldn't be able to survive in the cold winter due to temp and the fact that predators like wolves would be able to spot it easier from its color of its fur.
Note: Hope this helps, and I hope this is want it was asking. Good luck :)
Answer : (C) Hafnium is the most likely identity of the given substance.
Solution : Given,
Mass of given substance (m) = 46.9 g
Volume of given substance (V) = 3.5 
First, find the Density of given substance.
Formula used :

Now,put all the values in this formula, we get
= 13.4 g/
So, we conclude that the density of given substance (13.4 g/
) is approximately equal to the density of Mercury and Hafnium (13.53 and 13.31 g/
respectively).
According to the question the substance is solid at room temperature but Mercury is liquid at room temperature. So, Mercury is not identical to the given substance.
Another element i.e, Hafnium is the element whose density is approximately equal to the given substance and also solid at room temperature. And we know that the melting point of solid is high.
So, Hafnium is the most likely element which is the identity of the given substance.
CO2 and H2O react to form H2CO3 and two bonds are broken each in CO and H2O to form H2CO3.
<h3>What is chemical bonding?</h3>
Chemical bonding refers to the forces of attraction which hold atoms of the same or different elements together in order to form stable compounds or molecules .
Chemical bonding may be either ionic or covalent.
The greater the number of bonds in a compound, the more stable the compound.
During chemical reactions, bonds are broken and new binds are formed.
There are two bonds each in CO2 and H2O.
This, in the reaction between CO2 and H2O react to form H2CO3, , the number of bonds broken in H2O is two and in CO2 is two.
Learn more about chemical bonding at: brainly.com/question/819068
According to the illustration, the vanadium (V) oxide would be a catalyst.
<h3>What are catalysts?</h3>
Catalysts are substances that are utilized in reactions that are not themselves consumed in reactions but only speed up the rate of the reactions.
Catalysts speed up the rate of reactions by lowering the activation energy of the reactants.
Sulfur dioxide reacts with oxygen to produce sulfur trioxide. The vanadium (v) oxide is not consumed in the reaction. Thus it only serves as a catalyst.
More on catalysts can be found here: brainly.com/question/12260131
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There are different chemical agents which are used to study the heart rate of frog. Generally Ringer's solution is used to study frog's heart simulation. At different temperature, frogs heart speeds up or slows down while using Ringer's solution at experiment. Ringer's solution is mixture of salt solution which comprises of NaCl, KCl, CaCl2 and Na2CO3. Sometimes other chemicals like MgCl or antibiotics are also used as addition in Ringer's solution.
This solution is chiefly used to study in vitro experiments on organs and tissues like frog's heart.
Ringer's solution at 23 degree Celsius for normal heart rate
Ringer's solution at 32 degree Celsius, heart rate speed up and
Ringer's solution at 5 degree Celsius, heart rate slows down.
other chemicals also have significant effect in heart rate,
For example, Calcium ion in excess will slow down the heart rate, Atropine increases heart rate and digitalis slows down the heart rate.