It can be.
Zero is considered a significant digit when it is to the left or the right of the decimal point. It is also a significant digit when it follows a non-zero digit or when it is between two digits.
True
That is correct.
No, a leading zero is NEVER a significant digit.
If I understand this convoluted sentence correctly, then think it is true.
The thousands digit is 4 left of the decimal point and the ones digit is the digit to the left of the decimal point. In a whole number the decimal point is not written and can be considered as "hiding" after the last digit - the ones digit.
All digits are significant in this case. Any digit after a decimal point is a significant digit.
A zero is not considered a significant digit when it is used as a leading zero in a decimal number. For example, in the number 0.0045, the leading zeros before the 4 and 5 are not significant; only the digits 4 and 5 are significant. In this case, the leading zeros merely indicate the position of the decimal point.
All digits between the first non-zero digit and the last non-zero digits are significant. Some would argue that trailing 0s are significant since they are an indication of the precision of the number.
A significant digit is generally considered to be any non-zero digit, as well as zeros that are between non-zero digits or to the right of a decimal point after a non-zero digit. Zeros to the left of the first non-zero digit are not significant. Therefore, when considering significant digits, the position of the digit (left or right) matters, especially in relation to decimal points and the presence of non-zero digits.
The number 0.001 has one significant figure. The leading zeros before the digit "1" are not counted as significant figures, as they only serve to position the decimal point. Therefore, only the digit "1" is considered significant in this case.
All digits between the first non-zero digit and the last non-zero digits are significant. Some would argue that trailing 0s are significant since they are an indication of the precision of the number.