Any measurement is considered an approximate value?

No.

An approximate number is one that does have uncertainty. A number can be approximate for one of two reasons: The number can be the result of a measurement. For example a certain instrument capable of measuring to the nearest 0.1 cm may measure the length of a certain bolt to be 8.6 cm.

Smoking damages the respiratory system by inhalation of a foreign substance, that is absorbed and residue is left behind on our lungs sponge like substance. the gas that is inhaled also increase your blood pressure and dilates your blood vessels. also the process of inhaling and exhaling the smoke it causes irritation to the throat and mouth. smoking can cause lung cancer and other respiratory and circulatory diseases.