4 significant digits, decimals=2. All zeroes which are both to the right of the decimal point and to the right of all non-zero significant digits are themselves significant. Here each number is rounded to four, three, and two significant digits.
Example:
i) 1000 has one significant digit
ii) 0.000350 has three significant digits
iii) 560 has two significant digits. The last zero is just a placeholder.
