How do we know it's binomial? Well, it's made up of 500, it's a finite number of trials right over here. The probability of getting a defective chip, you could view this as a probability of success. It's a little bit counterintuitive that a defective chip would be a success, but we're summing up the defective chips. So we would view the probability of a defect, or I should say a defective chip, it is constant across these 500 trials, and we will assume that they are independent of each other, 0.02. You might be saying, hey, well, are we replacing the chips before or after? But we're assuming it's from a functionally infinite population, or if you wanna make it feel better, you could say, well, maybe you are replacing the chips.