In what state of matter does oxygen exist at room temperature

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change? work power gravitational energy chemical energy

In a voltaic cell, electrons flow from the (positive/negative) to the (positive/negative) terminal.

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?