Hello. I've got some sentences where I have to choose between Present Perfect and Continuous. Can somebody please write which answer is correct and explain WHY it is better than the other, or maybe say if BOTH answers are possible in some way? Thanks!

1) Where have you been? I have been waiting / waited for you all morning.
*For me "have been waiting" is better because of the expression "all morning", so emphasizing the time of waiting but "have waited" would be also OK.


2) I've visited / been visiting Science Museum lots of times, but I haven't been to Victiorua and Albert Museum opposite.
*Here also both seem possible to me.


3) Alice hasn't made / been making new friends very easily at her new school, but she's found a few friends from primary school.
*Here "hasn't been making" seems more appropriate to emphasize that it hasn't finished yet.


4) Jenny and Bess have met up / been meeting up with a group of school friends once a week to do their homework together. Their marks have really improved / have really been improving now.
*Here "have been meeting up" as it is not finished, recent and it repeats. The second "have improved" as it rather focuses on the result.


5) -Why has Holly been sitting / sat at the front of the class? -She can't see the board properly with those glasses.
*Here "has sat" as it wouldn't focus on the time.


6) I've started revising for the end-of-year exams. I've been feeling / felt really nervous about them.
*Here "I've been feeling" as it could repeat many times.


7) The drama club has been preparing / prepared the end-of-term play all year. The students have been doing / done everything without the teachers' help.
*Here "has been preparing" as it would focus on the period of time and "have done" to focus on the students' work. The other one "have been doing", I think, could be used to focus on the time and the fact that it may be unfinished.


8) Have you been paying / paid attention? What was the last question?
*I think "been paying attention" would be better to focus on the continuity.


9) She has been handing out / handed out leaflets before school for a month now, but no one has joined her photography club.
*Here "has been handing out" to focus on the time but I think that "has handed out" could be possible as well.


10) John has been revising / revised hard all week for his chemistry test.
*Here "has been revising" to focus on the time he had to spend.


11) Isabelle hasn't been learning / learned German very long, but she already speaks well.
*Again Present Perfect Continuous to focus on the time period


12) My class has come to Greece for ten days and for the last two days we have been staying / stayed in the mountains. A Greek ski instructor has been teaching / taught us to ski since we arrived.
*Here "have been staying" to emphasize the temporariness and "has been teaching" to say that he hasn't finished teaching us.


13) Kelly hasn't been watching / watched TV all day, though. She has been busy with her camera.
*Here "hasn't been watching" to emphasize time period.