Answer:
The correct answer is "C".
Homeostasis is the maintaining of stable internal conditions in the body of a living being, such as body temperature or heart rate.
The endocrine system is an organ in the body which is in charge of secreting hormones that regulate numerous functions in the body, including metabolism, growth, sexual function, sleep, and mood among others. It is an essential organ which contributes to the state of homeostasis in the body.
Explanation:
 
        
             
        
        
        
Explanation:
In Earth’s history before the Industrial Revolution, Earth’s climate changed due to natural causes not related to human activity. Most often, global climate has changed because of variations in sunlight. Tiny wobbles in Earth’s orbit altered when and where sunlight falls on Earth’s surface. Variations in the Sun itself have alternately increased and decreased the amount of solar energy reaching Earth. Volcanic eruptions have generated particles that reflect sunlight, brightening the planet and cooling the climate. Volcanic activity has also, in the deep past, increased greenhouse gases over millions of years, contributing to episodes of global warming
 
        
             
        
        
        
Boyle's law states that the relationship between pressure and volume of a fixed amount of gas at a fixed temperature is inversely proportional. This means that the higher the pressure, the lower the volume, in a proportional relationship. Therefore, of the statements listed, b: 'the temperature and the number of molecules must remain constant for the law to apply' and d: 'a<span>s the pressure of a gas increases, the volume decreases proportionally</span>' are correct.
        
             
        
        
        
Answer:
The correct statements are that the first calorimeter is reliable but not valid, and the second calorimeter is valid and reliable. 
Explanation:
The first calorimeter is reliable as the reading demonstrated by it is similar when each time the experiment is performed, however, the result attained is not correct, though it is reliable. On the other hand, the second calorimeter is both reliable and valid, as it is demonstrating the accurate results from time to time. This is valid as it is providing a similar result as that of the original readings.