If you answer this I’ll give brainliest 50+ points

The isotope oxygen-18 has been used to trace the origin of

1. structure A
2. reaction B
3. gas E
4. gas D

If you answer this Ill give brainliest 50 points The isotope oxygen18 has been used to trace the origin of 1 structure A 2 reaction B 3 gas E 4 gas D class=