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Why were traffic lights invented?

Duration: 07:35Views: 94.7KLikes: 469Date Created: Feb, 2022

Channel: Mystery Doug

Category: Science & Technology

Tags: k-5scienceelementary educationkids questions

Description: Are your kids wondering: Why were traffic lights invented? This question came from Ryan, a student from the United States. Like, share, and vote on the next question here: mysterydoug.com/vote

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