Answer:
Controls the movement of substances into and out of the cell.
Answer: polar solvent
Explanation:
Polarity can be said to mean, charge separation. Thus, polar solvents are solvents that have charge separation and the ability to solvate i.e dissolve ions.
A polar solvent molecule has slight electrical charge as a result of its shape. A typical and most common example is water, with an oxygen and two hydrogen atoms. The two hydrogen atoms are at an angle to the single oxygen atom. Water is the classic polar solvent. The oxygen atom tends to polarize electron density to itself.
The half life of carbon-14 is 5700 years. (Half life is the time taken by a radioactive isotope to decay by half of its original mass).
Let A₀ be the initial amount of carbon-14 that is found in living matter (t=0 years), to determine when there was 44.5% of A₀ left.
44.5 = 100 × (1/2)^n, where n is the number of half lives
0.5^n = 0.445
n = log 0.445/log 0.5
n = 1.168
But 1 half life is 5700 years
Therefore, the number of years will be 5700 × 1.168 = 6658.299725 years
≈ 6658.30 years