<span>Ultra violet light is the catalyst that converts 7-dehydrocholesterol to provitamin D3. Ultra violet light can be obtained from the sun. The conversion happens when UVB light hits the skin (where 7-dehydrocholesterol naturally resides), gets absorbed, and us metabolized inside of the body.</span>
Answer:
A major characteristic of mixtures is that the materials do not chemically combine
Explanation:
Mixtures can be divided into those that are evenly distributed (homogeneous) and those that aren't (heterogeneous)
Answer:
Explanation:
From the given information:
At wavelength = 270 nm

At 270 nm
Suppose x is said to be the solution for the concentration of x and y to be the solution for the concentration of y;
Then:


Divide both sides by 200


Use l = 1cm (i.e the standard length)
Then;

<u>For 540 nm:</u>


since l = 1

Equating both (1) and (2) together, we have:

They are metric units of measurement.