Final answer:
The number 52.90 has four significant figures. Relevant rules for determining significant figures are applied, where non-zero digits and zeros that indicate precision after a decimal point are considered significant.
Step-by-step explanation:
The question relates to the concept of significant figures in numbers, which is an important aspect of measurements in sciences, particularly in chemistry and physics. Understanding significant figures is essential to correctly report the precision of a measured or calculated quantity.
The number 52.90 has four significant figures. The digits 5 and 2 are significant because they are non-zero numbers (rule 1). The digit 9 is significant as it is between two non-zero digits (rule 2). Moreover, the digit 0 is significant because it is at the end of the number after a decimal point (rule 5), indicating measure precision.
Let's look at the example provided:
- 5.87 has three significant figures based on rule 1, as all non-zero numbers are significant.
- 0.031 has two significant figures. The zeros before 31 are not significant as they are merely placeholders (rule 4), while the numbers 3 and 1 are significant (rule 1).
- 52.90 as mentioned previously, has four significant figures.
- 00.2001 has four significant figures. The leading zeros are not significant (rule 4), but the three zeros after the decimal and before the non-zero digit 1 indicate precision (rule 3), and hence they are significant along with the number 1 (rule 1).