I think the 'neutrino faster than light' debacle is out of the HSC scope. Maybe we will be tested on some time/length/mass dilation that has a similar setting 'a neutrino travels from a source 730km away from a detector in Italy at 0.99c', or something like that.
A reduction in the net income deficit means we're paying out less dividends, servicing less interest, etc. It is not buying less imports, that would be a reduction in the net goods component.
I'm the same age as you so the 'immature' thing isn't really an explanation.
http://www.nsi.tafensw.edu.au/Courses/CourseDetail.aspx?num=19361&sem=S1/2012&op=MS
That's the link to the Bradfield TAFE for HSC Studies.
Maybe, just maybe, revenue is before tax. So it actually *is* $1500, but it changes to $2000 after tax as net income... I don't do business studies so I'm not exactly sure :P
Economic expansion refers to an increase in economic growth. Thus, the government would gain more revenue as more people move into higher tax brackets (eco growth leads to increase wages) and unemployment would drop leading to less transfer payments.