What would happen to the magnetic field if she connects
the battery in the opposite direction?

the answer would be   dignified - apex

current and voltage can both be different in different parts of a circuit so it matters where you place the ammeter and voltmete

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.

total distance/total time

(85 + 82)/(5+3)

167/8

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