A、They are made from cheap materials. B、They are only about half an inch thick. C、They can be laid right on top of existing high

(3) Last week, France announced that the country will pave 621 miles of road with solar panels over the next five years, with the goal of providing cheap, renewable energy to five million people. Called "the Wattway," the roads will be built through joint efforts with the French road-building company Colas and the National Institute of Solar Energy. The company spent the last five years developing solar panels that are only about a quarter of an inch thick and are strong enough to stand up to heavy highway traffic without breaking or making the roads more slippery. (4-1) The panels are also designed so that they can be installed directly on top of existing roadways, making them relatively cheap and easy to install. France isn’t the first country to kick around the idea of paving its roads with solar panels. In November 2015, the Netherlands completed a 229-foot-long bike path paved with solar panels as a test for future projects. (4-2) However, this is the first time a panel has been designed to be laid directly on top of existing roads and the first project to install the panels on public highways.
Questions 3 and 4 are based on the news report you have just heard.
3. What was France’s purpose of constructing the Wattway?
4. What is special about the solar panels used in the Wattway?