Given: (52.6 cm)(1.214 cm) What is the product expressed to the correct number of significant figures?
1.
64 cm2
2.
63.9 cm2
3.
63.86 cm2
4.
63.8564 cm2

2.

63.9 cm2

Explanation:

All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.

Leading zeros are not consider as a significant figures. e.g. 0.06 in this number only one significant figure present which is 6.

Zero between the non zero digits are consider significant like 108 consist of three significant figures.

The zeros at the right side e.g 240000 are also significant. There are six significant figures are present.

When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.  For example,

The difference between 7.69 and 4.0.

7.69 - 4.0 = 3.7

When we multiply or divide the values the number of significant figures must be equal to the less number of significant figures in given value.

For example in given q:

52.6 cm × 1.214 cm = 63.9 cm²

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.