Final answer:
The answer with 4 significant figures is (E) both (A) and (D) have 4 significant figures.
Step-by-step explanation:
The answer with 4 significant figures is (E) both (A) and (D) have 4 significant figures.
In this question, we need to identify the answer option that has 4 significant figures. Significant figures are the digits in a number that carry meaning or contribute to the precision of the measurement. We count significant figures by looking at all the non-zero digits and any zeros between them.
Option (A) 0.004 has one significant figure because there is only one non-zero digit (4), and the zeros are not significant. Option (B) 1200 has two significant figures because there are two non-zero digits (1 and 2). Option (C) 0.0974 has four significant figures because all the non-zero digits (9, 7, and 4) are significant, and the zeros between them are also significant. Option (D) 4.721 has four significant figures because all the non-zero digits (4, 7, 2, and 1) are significant. Therefore, the correct answer is (E) both (A) and (D) have 4 significant figures.