hola, esta pregunta es bastante difícil pero está bien, no lo sé, lo siento :) :)
The key enzyme in the regulation of the citric acid cycle is citrate synthase. It functions in the mitochondria.
<h3>Citrate synthase and cellular respiration </h3>
Cellular respiration is a series of reactions that produce ATP by using the energy stores in the chemical bonds of foods.
Cellular respiration is divided into glycolysis, the citric-acid cycle and oxidative phosphorylation.
Citrate synthase is an enzyme found in the mitochondrial matrix, which is involved in the citric acid cycle.
Learn more about cellular respiration here:
brainly.com/question/2809259
<h2>
Hello!</h2>
The answer is:
The empirical formula is the option B. 
<h2>
Why?</h2>
The empirical formula of a compound is the simplest formula that can be written. On the opposite, the molecular formula involves a variant of the same compound, but it can be also simplified to an empirical formula.

We are looking for a formula that cannot be simplified by dividing the number of molecules/atoms that conforms the compound.
Let's discard option by option in order to find which formula is an empirical formula (cannot be simplified)
A. 
It's not an empirical formula, it's a molecular formula since it can be obtained by multiplying the empirical formula of the same compound.

B. 
It's an empirical formula since it cannot be obtained by the multiplication of a whole number and the simplest formula. It's the simplest formula that we can find of the compound.
C. 
It's not an empirical formula, it's a molecular formula since it can be obtained by multiplying the empirical formula of the same compound.

D. 
It's not an empirical formula, it's a molecular formula since it can be obtained by multiplying the empirical formula of the same compound.

Hence, the empirical formula is the option B. 
Have a nice day!
27.6 - 22.3 = 5.3; you simply subtract the old density from the new density.
This sounds very much like a chicken-egg problem.
The first thing that formed must be hydrogen nuclei. The only other alternative is that the atom was created instantly, and the nuclei sprang forth at the same time as the atom, meaning that neither was technically first. The logic is that an atom can’t form without a nucleus, but it theoretically could be created instantly.