Los elementos traza, como el hierro y el magnesio están presentes en los seres vivos en grandes cantidades

the answer is 11

Explanation:

The rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three. Remember that proportionality is a constant relationship or ratio between different magnitudes.

If the relationship between the magnitudes is direct, that is, when one magnitude increases, so does the other, the direct rule of three must be applied. To solve a direct rule of three, the following formula must be followed:

a ⇒ b

c ⇒ x

So,  

The direct rule of three is the rule applied in this case as follows: If the change in water level is 0.05 inches per hour, what is the change in water level after 24 hours?

change in water level=1.2 inches

To pass a decimal number to a fraction, you must:

Put the decimal number in a fraction above a 1. That is, the decimal number is the numerator, 1 the denominator.

Find an equivalent fraction. That fraction will carry in the denominator a 1, and as many zeros as decimals the number has.

Multiply the number above by that number.

Simplify the fraction.

Applied to this case would be:

Since the denominator was multiplied by 10, the decimal numerator is also multiplied by 10:

Simplifying the rational number (for this the numerator and denominator is divided by the same number, in this case by number 2), you get:

Finally, the change in the water level of the pond after 24 hours is 1.2 inches or what is the same  inches

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."