Unicellular organisms, cells perform all the basic actions and functions required for living like nutrition, respiration, reproduction etc.
In multicellular organisms, cells divide their tasks on the basis of "DIVISION OF LABOUR" to specialize in certain functions besides respiration etc. Like conduction in neurons, excitation in muscles, RBC production by bone marrow etc.
Drill cores from the ocean floor were dated and found to be very young compared to the age of the earth. This means the crust had to be formed recently, which can be explained by creation of crust at a spreading center.
Answer is: pressure of oxygen is 31,3 kPa.
The total pressure<span> of an ideal gas mixture is the sum of the </span>partial pressures<span> of the gases in the mixture.
p(mixture) = p(helium) + p(oxygen) + p(carbon dioxide).
p(oxygen) = p(mixture) - (p(helium) + p(carbon dioxide)).
p(oxygen) = 101,4 kPa - (68,7 kPa + 1,4 kPa).
p(oxygen) = 101,4 kPa - 70,1 kPa.
p(oxygen) = 31,3 kPa.
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C) is higher for nonpolar substances than for polar ones