Find the number of significant figures in the `4.51 xx 10^8`

Explanation

To find the number of significant figures in the number \( 4.51 \times 10^8 \), we can follow these steps:

### Step 1: Identify the digits in the number
The number given is \( 4.51 \times 10^8 \). We focus on the digits in the coefficient, which is \( 4.51 \).

### Step 2: Determine the significant figures
In the number \( 4.51 \):
- The digit '4' is a non-zero digit and is significant.
...