Answer:
See below
Step-by-step explanation:
Jerry's mother is worried that she might be overprotective. She allows him to go to the other beach alone. Since this story is all about growing up, it is an important first step that Jerry is allowed to go somewhere alone, enabling him to be more grown-up. She also has more trust in Jerry, a sign that Jerry's transformation has begun. She purchases swim goggles without demanding why he needs them. This event especially advances the plot of the story because it builds toward the main event of the whole story: swimming through the tunnel, Had Jerry's mother refused to buy the swim goggles, he wouldn't have been able to swim through the tunnel.
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