Action-reaction forces : select one:
a. may be at right angles.
b. always act on the same object.
c. always act on different objects.
d. sometimes act on the same object.

i think its B)... im not sure so dont take it seriously

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

= initial pressure

= final pressure = 2

= initial volume

= final volume = /4

= initial temperature = 20 c = 20 + 273 = 293 k

= final temperature = ?

using the equation