Answer : the correct answer is D.
Explanation :
As per the question, the pressure is given as 1 atm.
We know that atmospheric pressure is,
\(P=\rho gh\)
where, \(\rho\) is the density of mercury.
g is the acceleration due to gravity.
h is the height of mercury column.
The pressure is said to be 1 atm if the mercury column corresponds to 76 Cm at STP.
This can be written as 76 Cm of Hg.
we know, 1 Cm = 10 mm
Hence, 76 Cm = 76 × 10 mmHg = 760 mmHg
