The answer is d. The answer is that because both of them can reproduce that way.
A proton is the same as an H+ ion, and Arrhenius acids are the ones that release H+ in solution, so the answer is A
Ions have an extra or lost an electron. Isotopes have different numbers of neutrons.
This says four figures. The 4 figures you should use are 4546 with a peek at 7 to see what effect it will have on the 4 main figures.
45.467 rounds to 45.47
You round the 4th figure up one. You are not concerned about the decimal places in this question.
