单选题 Chokwe Selassie is on a mission to help drivers avoid potholes (路面坑洼). The eighth-grader got his inspiration on a recent morning, when his mother was driving him to school. Their ear was damaged as it went over a huge pothole in the middle of the street in their hometown of Jackson, Mississippi. "I decided I was going to do something about the pothole problem in my city," said Chokwe. His solution: an app that warns drivers when there is a pothole ahead.
Chokwe developed the app with his friends. "When the app detects a pothole, it is highlighted in red," Chokwe says. "And if you get close to the pothole, your phone will warn you with a beep." Drivers can also use the app to report any potholes they encounter, and to look for other routes they can take to avoid roads that have them.
The app relies on current available information about the streets of Jackson. "It works by using the city"s 311 call system, so it uses: information already stored in a database," Chokwe says. Through the call system, citizens dial 311 to report non-emergency problems—which include potholes. As Chokwe and his friends worked on the app, they also went street by street throughout the city. They determined that focusing on the 10 busiest streets in Jackson would give them a large enough sample size to test it.
Although the app isn"t yet available for sale, Chokwe is already looking for ways to improve it. The app remains limited to 10 streets in Jackson, but he hopes to add more, so that it includes every street in the city. And then he wants to go even farther. "I want to keep working on the app until it"s nationwide," Chokwe says.

单选题 Chokwe Selassie got the idea to develop the app from ______.

单选题 When you are close to a pothole, your phone will warn you with ______.

单选题 Drivers can also use Chokwe"s app to ______.

单选题 To develop the app, Chokwe and his friends ______.

单选题 We can learn from the last paragraph that Chokwe ______.