Answer:
Will it be hard to get a good grade in that class?
Step-by-step explanation:
I hope she does not assign too much homework, (needs a period not a comma to end the sentence)
Will it be hard to get a good grade in that class? (correctly asked question)
Do you think the class will be difficult! (is a question but has an exclamation mark)
Is Mrs. Smith a difficult teacher. (is a question but is missing the question mark, it has an exclamation mark instead)