Nei, det må hun ikke. Med Duo hun kan ta mobilen hennes og lære ute i naturen!
"... ta med mobilen sin og ..." (unless she's taking someone else's phone :)
Med Duo plus selv uten mobil data ;)
Why is "she has to study at home" wrong?
"Huset" refers to a specific house, but not necessarily her home.
Why not. "she must study in the house"?
That is also an accepted translation.