32.2
2 significant figures
there are 2 significant figures in 21000 2 & 1 are the significant figures.
0.48 has 2 significant figures and 0.4800 has 4 significant figures. The correct answer would depend on the device used to measure the string, and on the precision of that instrument.
If the zeros are significant figures then 900 is correct to 3 significant figures. If rounding off has occurred then the answer could be 1 sf or 2sf. For example : If the original number was 903 and rounding off to the nearest ten was required then 900 is correct to 2 significant figures. If the number was 927 and rounding off to the nearest hundred was required then 900 is correct to 1 significant figure.
0.081778 to two significant figures is 0.082
147.658 to two significant figures is 150.
Nothing
The correct answer is 2. The three zeros between the decimal point and the 1 are place holders but they are NOT significant digits. See, for example, the Wikipedia link.
32.2
all non zero digits are significant .2.zeroes betweenother significant.
Significant figures are very important when it comes to calculations. If the mass of an electron is 9.10939 x 10-31 then its significant figures are: 9 x 10^-31( correct 1 significant figure), 9.1 x 10^-31 kg ( correct to 2 significant figures), 9.11 x 10^-31 (correct to 3 significant figures), and 9.109 x 10^-31 (correct to 4 significant figures).
2 significant figures
There are two significant figures in 0.025.
there are 2 significant figures in 21000 2 & 1 are the significant figures.
The correct answer depends on what is known about the number 2610. If it is known to be correct to 3 significant figures, the correct answer is 2620. If it is known to be correct to 4 significant figures, the correct answer is 2622. If all the numbers are known to be accurate to at least 2 decimal places then the correct answer is 2621.92
0.48 has 2 significant figures and 0.4800 has 4 significant figures. The correct answer would depend on the device used to measure the string, and on the precision of that instrument.