Pressure Questions

• Can water stay liquid below zero degrees Celsius?
• How does the outer layer of skin cells on my finger detect when I am touching an object?
• When I bump one end of a long metal bar, the other end instantaneously moves. Can I use this to send messages faster than light?
• Why don't I burst cells in my rear when I sit down?
• Why don't I feel the miles of air above me that are crushing me down?
• Why is ice slippery?
• Why is ice slippery?
• Why is propane stored in household tanks but natural gas is not?