1. Multiple-choice question (This big question is ***6 small questions, each with 6 points and each with ***36 points. There are four options for each small question, and only one option is correct. please

Fill in the correct branch number in the corresponding position on the answer sheet.

1. Multiplies any two numbers in the set {1, 3,6,8}. What is the probability that the product is even?

a . 5/6 b . 2/3 c . 1/2d . 1/3

8. The eyesight of students in Grade Two of a middle school 100 was randomly selected, and it was found that the eyesight of all students was between 4.3 and 5.2. Now these data are divided into 9 groups, and their frequency distribution histograms are as follows. It is also known that the frequencies of the first four groups have become geometric series, and the frequencies of the last six groups have become arithmetic series, so there are students with visual acuity of 4.6-5.0.