Answer:
There are 3 significant figures.
Step-by-step explanation:
Significant figures:
All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
Leading zeros are not consider as a significant figures. e.g. 0.03 in this number only one significant figure present which is 3.
Zero between the non zero digits are consider significant like 104 consist of three significant figures.
The zeros at the right side e.g 2400 are also significant. There are four significant figures are present.
The number such as 10³ are not consider as significant. for example 1.23× 10² in this number there are only 3 significant number.
In given measurement:
3.57 × 10⁹
There are three significant figures.