[wail_poet]

الفرق هو 2.201 مللى متر

at first case
roh h for alc = roh h for water
so roh alc = 1000 x 10 ÷ 12.5 = 800 kg/m3


second case:
(roh x h)alc + (roh x h) Hg = (roh x h) water
27.5x800 + 13600 x h = 1000 x 25
so h = 0.2205 cm = 2.21 mm