Read the passage. Then explain how scientific research changed cell phones and how cell phones changed based on the needs, desires, and values of people.

Modern transportation made it easier for people to travel far from their homes, schools, and offices. But people needed to contact one another while traveling. Engineers working on telephone systems saw that the solution was a telephone that could travel with people. And so the first cell phone appeared in 1973. Early cell phones were very large, heavy, and expensive. Few people had one, and people could use them only to talk. Over time, cell phones became smaller as computer chips were made smaller. Further advances led engineers to design smartphones, which can be used to do much more than just make phone calls. Today, 96% of American adults have cell phones. Many of these are smartphones t of 1930 shunaciars that people use to play games, connect to the Internet, conduct business, and more.