Doing simple questions well mainly depends on being careful. I used to be like you. The last few questions are all right, but the choice of the blank space in front is a bit wrong. Since you can do difficult problems, you have mastered all the methods, but you are not careful enough. If you still have time to finish the paper, you can check it carefully several times. The recommended way is to cover the original answer with draft paper, and then calculate the question. If the result is different from the first time, analyze the problem-solving process twice to find the correct answer. I hope it helps you.