Answer
-167 Joules
Work Step by Step
The new condition, that U=100J at y=0, is irrelevant in this equation. No values are changed and the answer remains the same.
---ΔU=Mass×Acceleration of Gravity×ΔHeight
ΔU=(.2kg)(9.8m/s2)(1.5m-10m)
ΔU= -167 Joules