Input: Article: Because the states were preexisting political entities, the U.S. Constitution did not need to define or explain federalism in any one section but it often mentions the rights and responsibilities of state governments and state officials in relation to the federal government. The federal government has certain express powers (also called enumerated powers) which are powers spelled out in the Constitution, including the right to levy taxes, declare war, and regulate interstate and foreign commerce. In addition, the Necessary and Proper Clause gives the federal government the implied power to pass any law "necessary and proper" for the execution of its express powers. Other powersthe reserved powersare reserved to the people or the states. The power delegated to the federal government was significantly expanded by the Supreme Court decision in McCulloch v. Maryland (1819), amendments to the Constitution following the Civil War, and by some later amendmentsas well as the overall claim of the Civil War, that the states were legally subject to the final dictates of the federal government.

Now answer this question: Where can we find express powers?

Output: in the Constitution

Input: Article: While inert gas reduces filament evaporation, it also conducts heat from the filament, thereby cooling the filament and reducing efficiency. At constant pressure and temperature, the thermal conductivity of a gas depends upon the molecular weight of the gas and the cross sectional area of the gas molecules. Higher molecular weight gasses have lower thermal conductivity, because both the molecular weight is higher and also the cross sectional area is higher. Xenon gas improves efficiency because of its high molecular weight, but is also more expensive, so its use is limited to smaller lamps.

Now answer this question: Why is xenon gas not more widely used?

Output: more expensive, so its use is limited to smaller lamps

Input: Article: New Haven has a long tradition of urban planning and a purposeful design for the city's layout. The city could be argued to have some of the first preconceived layouts in the country. Upon founding, New Haven was laid out in a grid plan of nine square blocks; the central square was left open, in the tradition of many New England towns, as the city green (a commons area). The city also instituted the first public tree planting program in America. As in other cities, many of the elms that gave New Haven the nickname "Elm City" perished in the mid-20th century due to Dutch Elm disease, although many have since been replanted. The New Haven Green is currently home to three separate historic churches which speak to the original theocratic nature of the city. The Green remains the social center of the city today. It was named a National Historic Landmark in 1970.

Now answer this question: On what type of city plan was New Haven laid out upon the founding of the area?

Output:
grid plan of nine square blocks