Then, the question c) which of the listed systems are “most similar” to each another?

The answer provided for question B is not correct. I attempted to submit using that answer and the system told me the answer was not correct.

The board of an Internet startup company has fifteen members. If one person is to be in charge of researchnbspand another in charge of accounting, in how many ways can these two positions be filled?

Goofus and Gallant are at the popular submarine sandwich chain, Sub Direction. Sub Direction has twenty- seven different sandwich toppings including meats, cheeses, and sauces, and you can have as many of each as you like on your sandwich. If you put more than five toppings on your sandwich, you have to pay extra, so Goofus and Gallant just want the five. a) Gallant (rightly) believes that sauces should go at the top of the sandwich, followed by leafy greens, then cheeses, then meats. How many ways can Gallant construct his five-topping sandwich? b) Goofus is just going to inhale the whole sandwich anyway, so who cares what order the toppings are in, he says. How many sandwiches can Goofus make?