How many significant figures are there in : (a) 0.54 (b) 3.001 x 10^5 (c) 5.600

(a) 2 (b) 4 (c) 4

Explanation:

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

Rules for significant figures:

Digits from 1 to 9 are always significant and have infinite number of significant figures. All non-zero numbers are always significant. For example: 654, 6.54 and 65.4 all have three significant figures. All zero’s between integers are always significant. For example: 5005, 5.005 and 50.05 all have four significant figures. All zero’s preceding the first integers are never significant. For example: 0.0078 has two significant figures. All zero’s after the decimal point are always significant. For example: 4.500, 45.00 and 450.0 all have four significant figures. All zeroes used solely for spacing the decimal point are not significant. For example : 8000 has one significant figure.

As per question,

0.000054 has 2 significant figures.

3.001 x 10⁵ has 4 significant figures.

5.600 has 4 significant figures.

Scissors and a seesaw both cut things that’s the only comparison

Answer (d) the universe had cooled enough for atoms to combine, protons and neutrons were too far apart to form nuclei;