Integers ending in 0 are always ambiguous. It is not possible to tell whether this number is accurate to the nearest million (1 significant figures) or to the nearest integer (7 significant figures).
It is difficult to say with integers ending in zero. The number could be acurate to the units' place or to the millionths' place (or anything in between). Therefore, there could be 1 to 7 sf.
4
It has 3 significant digits.
3 significant digits.
It has two significant digits.
Five. All nonzero digits are significant and zeros in between significant digits are significant.
Five. All nonzero digits are significant and zeros in between significant digits are always significant.
Five. All nonzero digits are significant and zeros in between significant digits are always significant.
Five. All nonzero digits are significant and zeros in between significant digits are always significant.
Three significant digits.
50.4 has 3 significant digits.
There are 3 significant digits in 20.0