Answer:
- Le crayon est sur la table.
- La fille est sous la table.
- La carte est sur la table.
- Le gâteau est sur la table.
- Les devoirs sont dans la poubelle.
- L'ordinateur et l'imprimante sont sur le bureau.
Explanation:
Don't forget to read attentively about the plural and singular.
For number 4, it asks where the cake is, but just for one so you wrote the sentence correctly you just did a little mistake of making the "Le" in plural. And if the sentence was in plural you would write is like this
: Les gâteaux sont sur la table.
Same goes for the number 5, this one was plural not singular, so the "Le" would be "Les". If it were singular it would be written like this
: Le devoir est dans la poubelle.