Q. Let x1, x 2, also x3 is 0-1 variables whose values indicate whether the projects are not done (0) or are done (1). Which answer below indicates that at least two of the projects must be done?
Q. Suppose that instead of a faucet, a five-gallon container is used for filling the bathtub (assume a full container is next to the tub to begin with); it takes two hours to refill the container also return it to the bathtub. Illustrate what happens to the system over time?