Answer:
Both sodium and calcium.
Explanation:
The membrane potential is maintained inside and outside of the cell due to the unequal distribution of the different ions. This membrane potential difference is important for the generation of action potential.
The resting membrane potential is around +30 mV. This is due to the presence of potassium ions. The sodium and calcium ions must enter in the cell to change this membrane potential and generates the action potential in the body.
Thus, the correct answer is option (3).
The equation that shows the formation of chromium (ii) ion from neutral chromium atom is as follow
Cr ---> cr^2+ + 2e-
Cr^2+ is the chromium ion with oxidation state of two which is one of the common ion of chromium. Other common ion of chromium include chromium of oxidation state 6 and 3
Option B: Strength of chemical bonds
Hardness defines the strength, it can not be compared with surface roughness as a smooth surface can be harder or difficult to break than a rough surface. The mass and weight of a substance matters while comparing density of substance or how heavy it is but it is not directly proportional to the hardness of the substance. Thus, equal masses of two substance can not be considered equally hard. Hardness depends on the inter-molecular interaction or forces within a substance, if the inter-molecular interactions are strong or the strength of chemical bonds is strong then the substance is more hard.
Therefore, hardness is directly proportional to strength of the chemical bonds.
Answer:
The velocity of flow in 10in pipe is 4.16 ft/s.
Explanation:
Given that
Specific gravity = 0.8
Viscosity =0.00042
For pipe 1

For pipe 1

If we assume that flow in the both pipe is laminar
For laminar flow through circular pipe

So same pressure drop we can say that



So the velocity of flow in 10in pipe is 4.16 ft/s.