Answer:
1_El concierto de jazz es a las ocho de la noche
2_Inés y pancho estan preocupados porque el examen va a ser dificil
4_ No puedo salir a tomar el sol porque está nublado
7_ La motocicleta nueva es de David
9_ La piscina del hotél es grande
10_Es importante estudiar, pero tambien tienes que descansar
Explanation:
As a native spanish speaker I can assure you that a couple of these questions were correct but they marked as incorrect
1_ You responded 100% correctly
2_ Están--- you can be a "persona preocupada" but in this case they are preocupados because of the exam.
4_ You responded 100% correctly
7_ That is David`s motocycle so it cannot be. Es de David - Es su motocicleta
8_ Yo estoy or estoy is a correct answer. stoy does not exist
9_ It is correct for me but we would problably say "es grande y bonita"
10_ Es importante estudiar. You cannot say Está because it would not make any sense. It would make sense though in many situations
