Step-by-step explanation:
Well if you dont understand something ask a teacher for help or study on a topic that you struggle with for example math try looking up different math questions and solving them or ask a teacher is you can have pratice questions or problems then show it to him/her so they can check to see if you are right. Hope that help unless you dont understand a certain question that I might have missed.
The third one is the answer
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Answer:
it will go up as all the groups will be removed from lower side reducing it's weights
I think the correct answer is 17