Identify two technologies that can be used to find the locations of objects.
Identify the type or types of waves each technology uses.

Sound energy is produced when an object vibrates. examples are 1- a balloon popping2-a whistle3- a waterfall

I'm not sure what your asking buddy.. but i know that you can weld two peices of steel by pure force and pressure.

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current