Which of the following numbers is correctly rounded to three significant figures, as shown in brackets?
a. 12,556 [12,500]
b. 4.5671 × 10^-9 [4.567 ×10^-9]
c. 3.00072 [3.001]
d. 0.006739 [0.00674]
e. 5.4589 × 10^5 [5.459 ×10^5]

D is correctly rounded to three significant figures.

Explanation:

A is incorrect because although it has 3 significant figures, it is rounded incorrectly. The correct answer would be 12,600.

B is incorrect because is rounded to 4 significant figures instead of three.

C is also incorrect because is rounded to 4 significant figures instead of three.

D is correctly rounded to three significant figures.

E is also incorrect because is rounded to 4 significant figures instead of three.

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.