Which TWO statements describe behaviors of particles that are related to the physical properties of the materials?
A. They allow electrons to move freely between them.
B. They do not easily form bonds with atoms of other elements.
c. They change their positions relative to one another.
D. They combine with oxygen atoms to form a new substance.

In the circuit, the switch s has been open for a long time and r = 125 kohm. it is then suddenly closed. (a) determine the time constant before the switch is closed. s (b) determine the time constant after the switch is closed. _ s (c) let the switch be closed at t = 0. find the current in the switch as a function of time. (use t for time. express your answer in milliamps and seconds.) i(t) =_