Can you please help with me with these Geology questions?

[Iphoneuser]

Using the LOWEST and HIGHEST single temperatures, the temperature increase in this time series would be:

http://img72.imageshack.us/img72/4949/19121974nc7.jpg

1) about 0.5 degrees
2) about 0.8 degrees
3) about 0.4 degrees
4) about 0.3 degrees

Use your mouse to click on the YEAR on the bottom axis where sea levels were at the zero average. Use the solid regression line to decide.

http://img509.imageshack.us/img509/2990/sealevel1wr6.jpg

About where would I select?

[bustersmycat]

the range of temps is about 0.8. the difference between the two temps indicated by red arrows appears to be about 0.3

Sea level according to the second chart was at " 0 " at around 1968.

Diagrams like these tell me that global warming is primarily a natural phenomenon and not caused by man's industrial activity, which is probably exactly the opposite of what you are being taught. Of course, that is just my interpretation.