Both atm and mmHg are pressure units. mmHg is millimeters mercury, in this pressure is calculated by the height of mercury level. 1 atm is equivalent to 760.0 mmHg therefore 0.250 atm is equivalent to - 760.0 mmHg/atm x 0.250 atm pressure in mmHg is - 190 mmHg
Sexual reproduction just means combining genetic material from two parents. Asexual reproduction produces offspring genetically identical to the one parent.
