The answer is: massive stars create a lot of heavier elements. They produce much of the carbon and oxygen which is hugely important for humans and water respectively.
Answer:
0.0556 mL of 90 M HCl would be taken and 9.944 mL distilled water added to make 0.5 M, 10 mL HCl solution.
Explanation:
From the dilution equation:
<em>Initial molarity (m1) x initial volume (v1) = final molarity (m2) x final volume (v2).</em>
In this case, m1 = 90 M, v1 = ?, m2 = 0.5 M, and v2 = 10 mL
v1 = m2 x v2/ m1 = 0.5 x 0.01/90 = 0.0000556 L
v1 = 0.0556 mL
This means that the initial volume of 90 M HCl to be taken is 0.0556 mL. Since the final volume to be prepared is 10 mL,
10 - 0.0556 = 9.944 mL
<em>Hence, 0.0556 mL of 90 M HCl would be taken and 9.944 mL distilled water added to make 0.5 M, 10 mL HCl solution.</em>
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Answer:
d. a system that enhances the destruction of bacteria through the activation of mast cells, lymphocytes, and phagocytes
Explanation:
Mast cells are white blood cells (i.e., lymphocytes) that form part of the immune system. These cells form part of the first line of defense against pathogenic organisms. Some of the most important phagocytic cells that function to protect the body by ingesting pathogenic agents (e.g., harmful bacteria) include mast cells, monocytes, neutrophils, macrophages and dendritic cells. In this regard, it is important to highlight that mast cells are similar to basophil granulocytes (another type of lymphocyte), and they are derived from hematopoietic stem cells.