Answer:
The correct answer is: <em>C. Increased average lifespan to 78 in the US.</em>
Explanation:
Science has impacted human health by increasing the average lifespan to 78 in the US. Over the last couple of decades, the life expectancy of Americans has increased significantly than what it was 200 years ago. This can be attributed to:
1. Vaccinations- Since the invention of vaccinations, diseases such as tuberculosis, cholera and polio which were major causes of death 200 years ago have virtually been eradicated in the US.
2. Abundant and safer foods available- Commercial and large scale farming has made a wide variety of nutritious foods easier to obtain.
3. Improved sanitation- Safer drinking water, sewage treatment and stricter food inspection has significantly reduced the rate of illnesses due to poor hygiene and sanitation.
In these ways, science has impacted human health by increasing the average lifespan to 78 in the US.
KCl + AgNO
3
→
KNO
3
+
AgCl
Explanation:
Formulas for the compounds:
KCl
:
potassium chloride (reactant)
AgNO
3
:
silver nitrate (reactant)
KNO
3
:
potassium nitrate (product)
AgCl
:
silver chloride (product)
KCl + AgNO
3
→
KNO
3
+
AgCl
If the compounds are in aqueous solution, then their physical states could be added.
KCl(aq) + AgNO
3
(
aq
)
→
KNO
3
(
aq
)
+
AgCl(s)
Answer:
<u>B. Animals do not use carbon dioxide as an energy source; they use carbohydrates.</u>
Explanation:
The most readily form of energy that an animal requires is carbohydrate molecules. Monosaccharide carbohydrates can be easily broken down and hence are the best sources of energy. Carbohydrates are broken down in the process of cellular respiration to generate ATP. ATP is the energy driving molecule which is required by every cell of an organisms body to carry out its normal metabolic functions. Hence, animals use carbohydrates as a source of energy, not carbon dioxide.