When can liquid water remain above 100 c?

Well,

Typically, a substance is under 1 atmosphere of pressure, or 1 atm.  More than 1 atm means there is more pressure than that which the earth's atmosphere exerts on an object near the surface of the earth.

If a liquid is given enough energy, and the atmospheric pressure remains constant, the liquid will turn into a gas.  In the case of water, it will turn into water vapor at 100 °C.  However, if you increase the pressure to greater than 1 atm, the water will be pushed together, keeping it liquid.

No because scientist are still changing there mines today so they are not correct to this day

M= 700 kgvalue of g( gravity) is constant = 9.8 m/s² or 10 m/s² w = mg = 700*9.8 = 6860n or 6.680*10³ n