Image in Answer 1 from Wikimedia Commons Commons https://commons.wikimedia.org/wiki/File:San_Francisco_Ferry_Building_20…
License: Creative Commons Attribution-Share Alike 4.0 International
Attributed to: Dllu
Image in Answer 2 from Wikimedia Commons https://commons.wikimedia.org/wiki/File:Coit_tower_-_panoramio_(1).jpg
.jpg){kind=link}
License: Creative Commons Attribution 3.0 Unported
Attributed to: 巫迪文
Imgae 3 in Answers is from Wikimedia Commons https://commons.wikimedia.org/wiki/File:Transamerica_Pyramid_(168703507…
.jpg){kind=link}
License: Creative Commons Attribution 2.0 Generic
Attributed to: Tony Webster from Minneapolis, Minnesota, United States
Image in Answer 4 is from Wikimedia Commons https://commons.wikimedia.org/wiki/File:Dutch_Windmill,_Golden_Gate_Par…
License: Creative Commons Attribution-Share Alike 4.0 International
Attributed to: Hu Nhu
Image in the Explanation is from Wikimedia Commons https://commons.wikimedia.org/wiki/File:San_Francisco_Ferry_Building_(c…
.jpg){kind=link}
License: Creative Commons Attribution-Share Alike 4.0 International, 3.0 Unported, 2.5 Generic, 2.0 Generic and 1.0 Generic
Attributed to: JaGa