1500 x 2^t = 0
Sasini's answer would be correct if the question involved t^2. However, it has 2^t, so the only way this could be zero is if t is minus infinity.
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1500 * 2^t = 0
2^t =0/1500
2^t =0
t =0
now all of time we can square root of 0 is 0.
so that answer is 0. i thnk itz a gd queston.