NEED HELP. BRAINLIEST FOR BEST ANSWER!

Answer:
1. 2 H2 1 O2 and 2 H2O
2. 2 THEN 2
3 1 THEN 2
4. 2 THEN 7 THEN 4 THEN 6
5. 1 THEN 1 THEN 1 THEN 2
Explanation: