Answer:
Here are a few examples:
Volcanic eruptions.
Retreat of glaciers.
Flooding accompanied by severe soil erosion.
Landslides.
Nuclear explosions.
Oil spills.
Abandonment of a manmade structure, such as a paved parking lot.
Explanation:
Answer: A: Its fertile oases enabled farmers to grow enough food for themselves and for sale.
Explanation: The Arabia region is a region located within the Arabian desert. A desert is an area of extreme heat, often dry weather condition with barren lands that cannot support agriculture and food production. An oases on the other hand is a region of luscious, cultivate-able land within a desert.
Food is one of the most important basic needs of man and hardly can anyone survive without food for more than twenty days. Hence, the presence of oases within the otherwise dry environment of the Arabia region is a major protection against death from hunger.
Taking a closer look at other options, none of them guarantees food supply and income to the Arabia region unlike food production in oases. Hence, the fertile oases is really the most important factor that serves as protection in the region's history.
Correct option: A
<span>Saturated fatty acids are those that have all single bonds except for the keto carbon of the carboxylic group. Unsaturated fatty acids are those that at least have one double bond between the carbons. If the fatty acid has only one double bond, it is referred to as monounsaturated.</span>
Answer:
A
Explanation:
The energy carried by electromagnetic waves is sometimes referred to as radiant energy. Electromagnetic waves do not require a medium for propagation hence they can travel through vacuum and are known to transmit enormous amount of energy.
Electromagnetic waves transmit energy away from the source of the wave. Hence the answer chosen in the answer section above.
Answers:
A. 50-70% - neutrophils
B. 20-40% - Lymphocytes
C. 2-8% - monocytes
D. 1-4% - eosinophils
E. < 1% - basophils
Explanation:
The blood differential test is used to estimate the percentage of each class of white blood cell (WBC) present in the blood and to indicate the presence of abnormal or immature cells.
The Test is Performed by taking of blood sample which is smeared onto a glass slide, then it's stained with a unique dye to indicate the class of white blood cells.
The Five class of white blood cells are
Neutrophils
Lymphocytes (B cells and T cells)
Monocytes
Eosinophils
Basophils
The different class of white blood cells are given as a percentage:
Neutrophils: 40% to 60%
Lymphocytes: 20% to 40%
Monocytes: 2% to 8%
Eosinophils: 1% to 4%
Basophils: 0.5% to 1%
Band (young neutrophil): 0% to 3%
