Answer:
After 12 seconds, the area enclosed by the ripple will be increasing rapidly at the rate of 1206.528 ft²/sec 
Explanation:
Area of a circle = πr²
where;
r is the circle radius
Differentiate the area with respect to time.

dr/dt = 4 ft/sec
after 12 seconds, the radius becomes = 
To obtain how rapidly is the area enclosed by the ripple increasing after 12 seconds, we calculate dA/dt


     dA/dt = 1206.528 ft²/sec
Therefore, after 12 seconds, the area enclosed by the ripple will be increasing rapidly at the rate of 1206.528 ft²/sec 
 
        
             
        
        
        
Answer:
Natural selection is a simple mechanism that causes populations of living things to change over time.  Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success.
 
        
             
        
        
        
Answer:

Explanation:
As in any sample you will have 75.8% of Cl-35 iosotopes and 24.3% of Cl-37 iosotopes you can get the average atomic mass as:

 
        
             
        
        
        
Answer: Electromagnetic radiation
Explanation:
Electromagnetic radiation is a combination of oscillating electric and magnetic fields, which propagate through space carrying energy from one place to another.
To understand it better:
This radiation is spread thanks to the electromagnetic fields produced by moving electric charges and their sources can be natural or man-made.
It should be noted that the energy of electromagnetic radiation can vary and depending on its frequency it can be useful for various situations.
 
        
             
        
        
        
1. In 2010-2011, the temperature decreased. In 2011-present, the temperature started increasing. From 390 to 405+
2. As the more carbon dioxide increases the temperature also increases with it.