Answer:
0.001574 in scientific notation is 1.574 × 10^-3
Explanation:
All numbers in scientific notation or standard form are written in the form m × 10n, where m is a number between 1 and 10 ( 1 ≤ |m| < 10 ) and the exponent n is a positive or negative integer. 
 
To convert 0.001574 into scientific notation, follow these steps: 
 
Move the decimal 3 times to right in the number so that the resulting number, m = 1.574, is greater than or equal to 1 but less than 10 
Since we moved the decimal to the right the exponent n is negative 
n = -3 
Write in the scientific notation form, m × 10n 
= 1.574 × 10^-3 
Therefore, the decimal number 0.001574 written in scientific notation is 1.574 × 10^-3 and it has 4 significant figures.
Hope this helped!!!