Which equation best represents the process of photosynthesis? 
 1.6CO 2 + 12H 2 O → light + C 6 H 12 O 6 + 6O 2 + 6H 2 O 
 2.6CO 2 + 12H 2 O + light → C 6 H 12 O 6 + 6O 2 + 6H 2 O 
 3.C 6 H 12 O 6 + 6O 2 + 6H 2 O → light + 6CO 2 + 12H 2 O 
 4.C 6 H 12 O 6 + 6O 2 + 6H 2 O + light → 6CO 2 + 12H 2 O