No flaw. The argument tells us that a dishwasher that doesn’t use energy efficiently or clean pans effectively is not well engineered, and that no available dishwasher uses energy efficiently or cleans pans effectively. That means we can validly conclude that no available dishwasher is well engineered!

No flaw. It’s definitely possible that Kameko’s lack of hat could cause her to catch a cold! Unlike the stimulus, (B) doesn’t reach a certain conclusion: it says that “it is possible” for Kameko’s hatlessness to cause her to catch a cold, whereas the stimulus definitively states that we can make a car that does both.

Wrong flaw. Unlike the stimulus, Susan and Nathan state definitively that it’s cold and snowing outside (respectively), not that it’s possible that it’s cold and snowing outside. That’s a fundamental difference between the structure of (C) and the structure of the stimulus: one has premises that deal in certainty; the other, in possibility.

The argument tells us that two things are possible: writing a best-selling novel and writing a novel that appeals to critics. Because both of these things are independently possible, the author concludes that both can be done together, within the same novel. This is the same hasty generalization flaw we saw in the stimulus: While it may be possible to do each of these things individually, there’s no support for the claim that it’s possible to do them together in one book!

Wrong flaw. Unlike the stimulus, (E) says that machines with the qualities in question already exist, and that it’s definitely possible to make a machine that has both qualities. The conclusion is still invalid (we can’t say that a machine will exist just because it could), but in a different way: the stimulus’ premises are about possible cars, not existing cars. Also, the stimulus’ conclusion is that it’s possible to combine both qualities into one car, whereas in (E), the ability to make a combination machine is a premise and the certainty of a combination machine is the conclusion.