Assume you want to play a game and the probability of winning the game is 7%. You pay $1 to play this game. If you win, you get $20 back (i.e., $19 net earning); if you lose, you get nothing back (i.e., $-1 net earning). Assume that you play this game 100 times, what is the probability that your total net earning is below $0? Assume that your net earnings follow a normal distribution, what are the mean and standard deviation?