10. how come the In’tl date line +some standard time zones dont travel perfect north to south?

Answer 1

It is political.

Some countries don't want part of their country to be in different time zones. So the lines are adjusted to meet the wants of the various countries. In some cases lines are adjusted farther West to allow more daylight time in the evening.

See Map: http://www.worldtimezone.com/

Answer 2

If all time zone lines were straight, then they would divide nations and their regions and states. For instance, the Intl Date Line conveniently divides the Bering Sea between Alaska and Russia. In the south Pacific, the IDL keeps national territories together, such as Samoa, Tuvalu and Kiribati.

This solution is the most practical.

Answer 3

Commerce has something to do with it but politics and local climate does to.

For example here in the U.S. Arizona doesn't change their clocks for daylight savings time. They don't want more sunlight because its really hot out there. Changing the clocks would limit the real ability to do outside work.

There is also a weird thing in Illinois in the US where some areas want daylight savings and some don't. I believe the time zone runs right through Illinois?

Answer 4

Most individual countries in the world are not as large as the United States, Russia, China, or Australia where you have 4 or more 'time zones' crossing your country due to its' physical land mass; so for geo-political reasons they adjusted the time and date lines to include their people into one 'date' and in most cases one 'time zone'.
The areas of Micronesia and Indonesia "bent" the date/time lines in both directions (East & West) to include their Islands under a single time zone.
That same 'trick' was also used by the State of Alaska and the Kamchatka area of Western-most Russia to include their outlying islands under one time zone & date line.

Answer 5

Probably convenience and for commerce. They would not want the line to pass through any major cities or countries so that one half is say, Thursday, and the other half is Friday. Same for time zones.

Answer 6

This is so countries don't get two or more different time zones. However some countries still encounter this problem, for example USA.

Answer 7

cities would be divided and even houses would be divided (it's 2pm in the kitchen but 3pm in the laundry room), etc.