Although 1013.25 mb (760 mm Hg) is considered to be the standard atmospheric pressure at sea level, it does not mean that the pressure at this level has this value, actually this being 1011 mb.
The information that a foliated metamorphic rock provide about the conditions it was formed under are:(for many diffrent rocks like Phyllite and Amphibolite)
you can tell by its features like if its smooth and sleek or if its rough and bumpy those physical features.
11.0 kg = (11.0 kg)(1000 g/kg) = 11000 g
(11000 g)/(1400 cm3) = 7.857 g/cm3
Simplified = 7.86 g/cm3