Question

the number $1.050 \times 10^9$ has how many significant figures?
\bigcirc 2
\bigcirc 3
\bigcirc 4
\bigcirc 9
\bigcirc 13

Explanation:

Step1: Recall significant figure rules for scientific notation

In scientific notation \( a \times 10^{n} \), the significant figures are determined by the digits in \( a \). Leading zeros are not significant, but zeros between non - zero digits and trailing zeros after the decimal are significant.

Step2: Analyze the number \( 1.050\times10^{9} \)

For the number \( 1.050 \), the digits are 1, 0, 5, 0. The 1 is non - zero, the 0 between 1 and 5 is significant (it is a zero between two non - zero digits), the 5 is non - zero, and the trailing zero after the decimal is significant (it shows the precision of the measurement). So we count the significant figures: 1, 0, 5, 0. That's 4 significant figures.

Answer:

4 (The option corresponding to 4, if we assume the options are presented as "4" among the choices. If the options are labeled, for example, if the option "4" is one of the radio buttons, then the answer is the option with 4. Since in the given options, one of them is 4, the correct answer is the option with 4, e.g., if the options are numbered as per the radio buttons, the third option (assuming the first is 2, second 3, third 4, etc.) which is "4".)