the answer is A. Imperfecto progresivo.
The progressive imperfect is used to express something that was taking place in the past. It is formed using the verb to be in past (in this case: estaba) plus the verb ending in ing (ando, endo, in this case: cantando). It is mainly used for: on-going actions that were happening in the past.
Answer:
A displacement is a vector whose length is the shortest distance from the initial to the final position of a point P. It quantifies both the distance and direction of an imaginary motion along a straight line from the initial position to the final position of the point.
Explanation:
Yo, yo, tu. I hope theyre right