1.In a survey of 3630 college students,1162 stated that they

1.In a survey of 3630 college students,1162 stated that they cheated on an exam.If two students are randomly selected,find the probability that they both cheated on the exam.
2.In a game of dice,a play receives $5 if the sum of dots on the dice is 4,$8 if the sum of the dots on the dice is 10.Otherwise the player loses $2.Find the expected value of the net gain of the palyer.
第一题是概率,第二题是期望.紧急!最好有解题过程.