#### Answer

a) Up
b) .4 turns

#### Work Step by Step

a) The time is too little each day, so the period is too little. In order to adjust the clock, therefore, it is necessary to move the nut up in order to make the period smaller, for length is directly related to how long a period is.
b) We first must find where the center of the mass is originally:
$ l = 15-1.92-\frac{6.35}{2}=9.905 \ cm \ m$
Thus, we can find the new length:
We find the current period:
$T = \frac{86940}{43200}=2.002 \ s$
Thus, we find:
$l = 9.905\times (\frac{2}{2.002})^2=9.88 \ cm$
$\Delta l = 9.88-9.905=.0206\ cm$
Since there are .05 centimeters per turn, this means that it should be turned about .4 turns.