Answer:
Rebecca and Brian each have 40 batteries, making a total of 80 batteries.
Explanation:
Rebecca:
Rebecca has 4 packs of batteries, and if each one contains 10 batteries, then she has 40 batteries.
Brian:
Brian also has 4 packs of batteries, each one contains 10 batteries, so he also has 40 batteries.
In total, they have a combined 80 batteries. hope this helps ;)