That would be a minor 3rd as D (in the key of D major anyway) is the root or tonic, and F is the 3rd(minor).
Answer:
There is many. I would say Romeo and Juliet because your teacher might like that. If you don't like it, you can always watch things like peter pan.
It starts slowly, with only a few instruments. Gradually speeds up the tempo, gradually gets louder, adding more instruments....but the same tune is repeated over and over again. The single the,e achieves unity. The tempo and dynamic changes (Loudness, speed) give is the variety.
It’s all good i don’t know why it’s flagging you