In most people's cognition, the difficulty of chemistry and biology is lower than that of mathematics and physics, but the core of the difficulty of the discipline is not the characteristics of the discipline itself, but the degree of differentiation that the subject needs to establish.
In the case of the same volume of arts and sciences, mathematics needs to take into account the receptivity of liberal arts and physiology students, and the requirements for thinking ability are too high, and the degree of discrimination cannot be formed among liberal arts students, so more emphasis is placed on the calculation proficiency formed by brushing the amount of questions, and its difficulty is more reflected in calculation than thinking.
Suppose there are 100 students, and these 100 students all choose mathematics, but 60 choose science, that is, they need to choose physics, and liberal arts students are also studying mathematics, but not physics, so the average level of physics students is higher, and the competitive pressure is greater.
Assuming that 20% of students in each subject can get 80%+ grades, mathematics needs to be ranked in the top 20 out of 100, physics needs to be ranked in the top 12 out of 100, and 60 people with stronger scientific thinking ability are ranked in the top 12, considering that there are also a few students with excellent scientific thinking ability among liberal arts students, which is equivalent to ranking in the top 15 out of 100 in mathematics.
Suppose 60 people choose physics, and only 45 people choose chemistry at the same time, and science students who do not choose chemistry are the group with relatively weak thinking ability, which is in the top 20% at this time, and the difficulty is greater than that of physics.
After the binding of physics and chemistry, most of the students who originally intended to be students of popular compositions need to choose between geography and biology, and geography has the characteristics of both metaphysics and low difficulty of assigning points, and eugenics are more willing to choose biology, so the student group of biology is smaller than chemistry, and the average level is also higher, and the difficulty is not lower than chemistry.