Final answer:
The number 2,804 contains four significant figures. Each digit in the number is significant as there are no leading or trailing zeros that would otherwise affect the count of significant figures.
Step-by-step explanation:
The number 2,804 has four significant figures. Significant figures are the digits in a number that carry meaning contributing to its measurement precision. This includes all digits except:
- Leading zeros, which merely indicate the position of the decimal point.
- Trailing zeros in a number without a decimal point, as they may or may not be significant.
- Spurious digits introduced, for example, by calculations that produce more digits than the precision of the input values warrants.
In 2,804, each digit is significant because none of them are leading or trailing zeros. For example, in the exercise solution where 450 has two significant figures and is written as 4.5 × 10² in scientific notation, while 450.0 has four significant figures and is written as 4.500 × 10². Similarly, in the expression 76.4 × 180.4, we limit our final answer to three significant figures because the first number, 76.4, has three significant figures.