I believe the answer is b. Tomas can decorate 16 gifts with 2 rolls of ribbon because you divide 34 into 2 and you get 17. and since you want to use all of the ribbon the best choice is 16 gifts. Btw plz don't report me if i get this wrong.
Hope this Helps!
Las válvulas distribuidoras pueden clasificarse en dos grupos means "The distributor valves can be classified into two groups"
Past tens would be participaron
Future tens participaran.
