A U tube is initially filled with mercury $(=13\mathrm{.}5103$ kg$$m$-3)$ to the

same height on both sides of the tube. A stopper with a pressure gauge

is then inserted on the right$-$hand side of the tube. Mercury is slowly

removed from the left$-$hand side of the tube until the level on the right$-$

hand side drops by $2=0\mathrm{.}10$ cm and the pressure gauge reads

$$gauge $=1500$ Pa$.$ The removal of the mercury is a quasistatic process

and the system is in excellent thermal contact with its environment.

$13)(4$ pts$)$ By how much does the mercury level drop on the left$-$hand side of the tube $1?$

A$.0\mathrm{.}11$ cm

B$.1\mathrm{.}2$ cm

C$.7\mathrm{.}4$ cm

D$.11$ cm

E$.76$ cm