Where does the lena river begin and end?

Why does sweden and norway have steep roofs

Can someone me choose a broad topic and area of focus i am really doing this as a tally to see which one most people pick ok water pollution global warming endangered species atmosphere for the !

The us and canadian governments are doing all of the following to combat environmental problems except a. encouraging the use of public transportation b. enacting clean water policies c. requiring emissions testing d. limiting animal populations in some regions