I am in karachi, because Karachi is a city and you can't be "at" a city. Saying I'm at only works if it a place such as a grocery store or a mall, but does not apply to cities or countries.
I believe the correct answers are rise; seems.
Its a big art history topic
All the sentences in a paragraph should be unified and coherent.
Answer: sentences
From the topic sentence to the concluding sentence, they need to be unified and coherent for the writer to truly get their point across as it was intended.
Hope this helps! :)
Attached you will find a file with the answers to the four questions provided.