Since the forces exerted on the box are equal and opposite in direction, the net force will be 0, so the box will not move.
A way to think of this is the equal forces in opposite directions cancel each other out, so the net force is 0.
300000-50000=250000
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The rule to find the term is: y=225-4x
you want to know the 82nd term which occurs when x=82 therefore
y = 225-(4 x 82) = -103
82nd term = -103