I believe Mendeleev formed his periodic table by atomic weight (nowadays we do it by atomic number) so he likely used those values.
Answer:
A) They are all acidic.
Explanation:
All 3 of those have acidic qualities in the drink.
X equals <span>2.76923076923</span>
Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value. The equation to describe the decay is
Nt=N0(1/2)

where N0 is the initial quantity, Nt is the remaining quantity after time t, t1/2 is the half-time. So work out the equation, t1/2 = t (-ln2)/ln(Nt/N0) = 11.5*(-ln2)/ln(12.5/100) = 3.83 days
Rris is how u right it Mg=? Because it ask u a question and then you put the equal sign and then you put the question mark because you don't know it yet