Did you even bother looking at the usyd website?
B. Commerce core units:
ACCT1001 Accounting 1A
ACCT1002 Accounting 1B
ECMT1010 Business and Economic Statistics A
ECON1001 Introductory Microeconomics
ECON1002 Introductory Macroeconomics
INFS1000 Business Information Systems Foundations
MKTG1001 Marketing Principles
CISS2001 Business in the Global Environment *
FINC2011 Corporate Finance I
WORK2218 People and Organisations
ECOF3001 Business Strategy
Source:
http://www.econ.usyd.edu.au/course/FH027.html
B. Economics core units:
ECON1001 Introductory Microeconomics
ECON1002 Introductory Macroeconomics
ECMT1010 Business and Economic Statistics A
ECMT1020 Business and Economic Statistics B
+ Major in Economics OR a major or an extended major in Econometrics and a minimum of 12 senior credit points in Economics
Source:
http://www.econ.usyd.edu.au/course/FH029.html
Differences:
*Core units for b commerce are greater in number and more diverse. This means that you have less electives than you would for b economics.
*In b economics, one of your two majors must be in either economics or econometrics, whereas for commerce you can choose any two majors you like.
Job prospects: if you major in economics under b commerce, there isn't much (if any) difference. Otherwise, the job prospects will depend on which majors you wish to pursue.