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.

Passage: The effects of local surface low pressure are extremely limited because upper-level subsidence still continues to block any form of air ascent. Also, to be protected against rain-bearing weather systems by the atmospheric circulation itself, the desert is made even drier by his geographical configuration and location. Indeed, the extreme aridity of the Sahara can't be only explained by the subtropical high pressure. The Atlas Mountains, found in Algeria, Morocco and Tunisia also help to enhance the aridity of the northern part of the desert. These major mountain ranges act as a barrier causing a strong rain shadow effect on the leeward side by dropping much of the humidity brought by atmospheric disturbances along the polar front which affects the surrounding Mediterranean climates.
what is blocked buy the surface low pressure?

Passage: Traditionally, Section 1983 was of limited use for a state prisoner under sentence of death because the Supreme Court has held that habeas corpus, not Section 1983, is the only vehicle by which a state prisoner can challenge his judgment of death. In the 2006 Hill v. McDonough case, however, the United States Supreme Court approved the use of Section 1983 as a vehicle for challenging a state's method of execution as cruel and unusual punishment in violation of the Eighth Amendment. The theory is that a prisoner bringing such a challenge is not attacking directly his judgment of death, but rather the means by which that the judgment will be carried out. Therefore, the Supreme Court held in the Hill case that a prisoner can use Section 1983 rather than habeas corpus to bring the lawsuit. Yet, as Clarence Hill's own case shows, lower federal courts have often refused to hear suits challenging methods of execution on the ground that the prisoner brought the claim too late and only for the purposes of delay. Further, the Court's decision in Baze v. Rees, upholding a lethal injection method used by many states, has drastically narrowed the opportunity for relief through Section 1983.
n what case did the Supreme Court allow Section 1989 to be used to challenge a method of execution?

Passage: The site where the Saint Petersburg Passage sprawls had been devoted to trade since the city's foundation in the early 18th century. It had been occupied by various shops and warehouses (Maly Gostiny Dvor, Schukin Dvor, Apraksin Dvor) until 1846, when Count Essen-Stenbock-Fermor acquired the grounds to build an elite shopping mall for the Russian nobility and wealthy bourgeoisie. Stenbock-Fermor conceived of the Passage as more than a mere shopping mall, but also as a cultural and social centre for the people of St Petersburg. The edifice contained coffee-houses, confectioneries, panorama installations, an anatomical museum, a wax museum, and even a small zoo, described by Dostoyevsky in his extravaganza "Crocodile, or Passage through the Passage". The concert hall became renowned as a setting for literary readings attended by the likes of Dostoevsky and Turgenev. Parenthetically, the Passage premises have long been associated with the entertainment industry and still remains home to the Komissarzhevskaya Theatre.
When was Saint Petersburg demolished?