I'm not from arts stream so I'm not sure what the available
combi are. However based on what you have chosen, it seems like you
have chosen an arts combi.
For science stream, the basics are 3H2s and 1H1, and the H1 is
the contrasting subject. This means that your 3H2s should be
science subjects and the H1 should be the art subject.
For instance, the most common science combi is: H2 Maths, H2
Physics, H2 Chemistry and H1 Econs.
If you were to choose the subjects you indicated, based on what
I know, there is an available combi that is:
H2 Maths, H2 Econs, H2 Geography, H1 Chemistry which is an arts
combi.
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As for your question regarding H2 Maths, regardless of H1/H2,
they both involve knowledge of both Emath and Amath.
Most people would advise you to go for H2 Maths as it opens far
more doors at the university level and furthermore, most of the
Singapore cohort takes maths at the H2 level, so if you were to
take maths at the H1 level, it is more likely that you will lose
out to them.
Of course, if you are completely sure that the courses you would
like to enter at University does not require H2 maths, then I guess
it's fine.
