Argument A: When Sputnik II was launched into space, it carried a Russian dog named Laika, which became the first living mammal to orbit the earth. Since dogs commonly live for more than 10 years, it follows that Laika lived in space for nearly a decade before her death.
Argument A is and all true premises. Therefore, Argument A is .

Argument B:

Every globe shows that the United States is in the Southern Hemisphere. Therefore, next year most American cities will probably be colder in July than in January.
Argument B is and all true premises. Therefore, Argument B is :-

Argument C:

Trains and airplanes are both popular ways to travel across the country. Since you can purchase a cabin in a sleeping car on a transcontinental railroad trip, it follows that there are sleeping cabins available on most transcontinental airline flights.

Argument C is and all true premises. Therefore, Argument C is .

Argument D:
Since there have never been any major earthquakes in the San Francisco Bay Area, it is unlikely that there will be a major earthquake in the San Francisco Bay Area anytime soon.

Argument D is and _ all true premises. Therefore, Argument D is .