1 significant figure. It can also be written as 4x10^6 (one sig fig)
Just the one and it is 4
4000000
One - the zeros are placeholders unless indicated.
There are four significant digits in the number 1.071.
This number has seven significant digits.
Three significant digits.
All four of the digits given are significant digits.
There are two significant digits in the number 83.
All numbers which are not "zero" are classed as significant digits. Therefore in the number 129 there will be three digits which are classed as significant.
Two. All nonzero digits are significant.
There are 2 significant digits: 5 and 4
All the digits are significant, so there are 5 significant digits.