3. (5 points) 10,000 rubber ducks are floated down a stream. 200 of the ducks are gold colored; the rest are yellow. Assuming they get thoroughly mixed during their passage, the number of gold ducks among the first 100 to cross the finish line has approximately (a) Bernoulli(0.02) distribution. (b) binomial(10000, 0.02) distribution. (c) normal(2, 1.96) distribution. (d) Poisson(2) distribution. (e) geometric(0.02) distribution. 4. (5 points) A simple random sample Vi, ..., Vso of 80 exponential(A) data has mean 4.35 and variance 15.89. As we have seen, the MLE for the distribution mean, u = 1, is a = V. The value of the Wald 95% confidence interval for / is (a) 4.35 + 1.960, 4.35 (b) 4.35 + 1.960 15.89 80 (c) 4.35 + 1.960 4.35 V80 (d) 13 1.35 + 1.960 4.35 V80x 15.89 + 1.960- 1 4.3580