Warsaw

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Warsaw City Sights: 

Jewish Ghetto Memorial
Warsaw Old Town
Auschwitz

For the solutions click here

Souvenirs for the Shopaholic Milestone: 

You should sell the Piece of the Chinese Wall from Beijing here as a City-to-do-task.

As you can see, I did not find a place to sell any of these items for a profit.

Items you might want to sell here for a profit: 

Keychain from Washington for 880
License Plate from Washington for 2760
FBI Shirt from Washington for 8110
Fabric from Kuala Lumpur for 9500

Jobs that are only available in Warsaw: 

As I write this, there is no City Expert job for Warsaw with a map
Dance Teacher
Geography Teacher - Poland
Marie Curie Fan
Ornithologist (there are more jobs with this name, but one is special for Warsaw)
Renaissance Scholar

Jobs that are only available in Europe: 

American Idol
Balkans Expert
Benelux Expert
Circus Artist
Expert in European Literature
Geography Teacher Europe

Passport:

Tourist Center: 

Renaissance Scholar

Only available in Warsaw

A common motif in Renaissance art was “The Annunciation”. But when is the Feast of the Annunciation of the Blessed Virgin, or “Lady Day” celebrated?

25th of March

A popular musical instrument during the renaissance was the spinet. What kind of instrument was it?

A piano

Marie Curie Fan

Only available in Warsaw

How did Marie Curie die?

Blood disease

In what did Marie and Pierre Curie perform most of their research?

Shack

Dance Teacher

Only available in Warsaw

In which time is the common waltz danced?

3/4 time

Quickstep is a fast version of the foxtrot. Which country does the dance Quickstep come from?

England

Ornithologist or Birdwatcher

It seems to me that the questions and answers to these two jobs are the same. 
Birdwatcher is available around the world, Ornithologist only in Warsaw. 
So you can get two job diploma's for this. 
Then is also a Ornithologist job in Lima, with different questions. You can find the answers I found fot that job below. 

Ornithologist (Warsaw) or Birdwatcher (World)

As of 2017, around how many bird species are extinct?

200

How fast can frigate birds fly?

260 MPH 

Geography Teacher - Poland

City Sights - Warsaw

Jewish Ghetto Memorial

(7 tickets)

The Jewish Ghetto Memorial is a monument in Warsaw, Poland, commemorating the Warsaw Ghetto Uprising of 1943 during the Second World War. It is located in the area which was formerly a part of the Warsaw Ghetto, at the spot where the first armed clash of the uprising took place. The monument was built partly of Nazi German materials originally brought to Warsaw in 1942 by Albert Speer for his planned works. The completed monument was formally unveiled in April 1948. The monument was raised in the square of Anielewicza Street, Karmelicka Street, Lewartowskiego Street and Zamenhofa Street. From August 1942 until the end of the Warsaw ghetto this was the last location of the Judenrat.