Ranked first, physics, because I don't study physics, so I feel the most difficult, as if electricity and work are the most difficult ~

Ranked second, mathematics, it should be analytic geometry, and there are many calculations (most of them are incomplete, don't worry, just for application).

Ranked third, chemistry, seems to be redox, skilled use of the periodic table of elements, and the most important experiment, this is the most difficult, including operation and calculation, the rest should be all right ~