Question

The respective number of significant figures for the numbers $23.023,0.0003$ and $2.1\times {10}^{-3}$ are :

• A. 5, 1, 2
• B. 5, 1, 5
• C. 5, 5, 2
• D. 4, 4, 2

Answer 1

Answer: (A)

5, 1, 2

Zeroes before a digit is not counted as a significant figure. In first number all digits are significant. In number second only 3 is significant all other zeroes are before digit therefore, not counted as a significant figure and numbers in powers are also not counted as a significant number, hence there are only 2 significant digits in the last number. Therefore, option (A)