This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Input: Consider Input: Passage: In the context of relativity, mass is not an additive quantity, in the sense that one can add the rest masses of particles in a system to get the total rest mass of the system. Thus, in relativity usually a more general view is that it is not the sum of rest masses, but the energymomentum tensor that quantifies the amount of matter. This tensor gives the rest mass for the entire system. "Matter" therefore is sometimes considered as anything that contributes to the energymomentum of a system, that is, anything that is not purely gravity. This view is commonly held in fields that deal with general relativity such as cosmology. In this view, light and other massless particles and fields are part of matter.

Output: What type of quantity is mass?

Input: Consider Input: Passage: Throughout the 1980s and 1990s, demand for a Scottish Parliament grew, in part because the government of the United Kingdom was controlled by the Conservative Party, while Scotland itself elected relatively few Conservative MPs. In the aftermath of the 1979 referendum defeat, the Campaign for a Scottish Assembly was initiated as a pressure group, leading to the 1989 Scottish Constitutional Convention with various organisations such as Scottish churches, political parties and representatives of industry taking part. Publishing its blueprint for devolution in 1995, the Convention provided much of the basis for the structure of the Parliament.

Output: Demand for a Scottish Parliament declined in what year?

Input: Consider Input: Passage: On 14 May 1955, the USSR and other seven European countries "reaffirming their desire for the establishment of a system of European collective security based on the participation of all European states irrespective of their social and political systems" established the Warsaw Pact in response to the integration of the Federal Republic of Germany into NATO, declaring that: "a remilitarized Western Germany and the integration of the latter in the North-Atlantic bloc [...] increase the danger of another war and constitutes a threat to the national security of the peaceable states; [...] in these circumstances the peaceable European states must take the necessary measures to safeguard their security".
Output: The USSR and eight other European countries formed the Warsaw Pact on what date?