A gas balloon is going up with a constant velocity of \( 10 \,\text{m/s} \). When this balloon reached a height of \( 75 \,\text{m} \), a stone is dropped from it and balloon keeps moving up with the same velocity. The height of the balloon when the stone hits the ground is ______ \( \text{m} \). \([ \text{Take } g=10 \,\text{m/s}^{2} ]\)
