5 of them.
3 significant digits because first zeros are just placeholders
Three. All nonzero digits are significant and zeros in between significant digits are always significant.
3
Two. All nonzero digits are significant.
There are 4 significant figures in 6.741.
Four
Two of them.
4
2.5000 has five significant digits and 104 has three significant digits. Therefore, the product should have three significant digits, and the answer is "260.". Note that the zero has to be made significant, so a decimal point is needed after the zero or you could put a vinculum (horizontal line) above the zero.
Five. All nonzero digits are significant and zeros in between significant digits are significant.
It has two significant digits.
3 significant digits.
It has 3 significant digits.
4 significant digits.
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.