Answer:
carbon + oxygen → carbon dioxide
Time required : 3 s
<h3>Further explanation
</h3>
Power is the work done/second.

To do 33 J of work with 11 W of power
P = 11 W
W = 33 J

Answer:
C) Use two batteries instead of one.
Explanation:
-Strength of an electromagnet depends on the electrical current which flows through the wires.
-Two batteries have a higher current than one and thus higher strength in the electromagnet.