(a) Equivalent head in water
$h_{water} = -s_{mercury} h_{mercury} = -13.6(0.254)$
$h_{water} = -3.4544 \, \text{m}$ answer
(b) Equivalent pressure in kiloPascal
$p = \gamma h = 13.6(9.81)(-0.254)$
$p = -33.89 \, \text{kPa}$ answer
(c) Absolute pressure for a barometric reading of 736.6 mm of mercury
$p_{abs} = p_{atm} + p_{gage}$
$p_{abs} = 13.6(9.81)(0.7366) - 33.89$
$p_{abs} = 64.39 \, \text{kPa}$ answer