Question: Hazards to aircraft include debris, nesting birds, and reduced friction levels due to environmental conditions such as ice, snow, or rain. Part of runway maintenance is airfield rubber removal which helps maintain friction levels. The fields must be kept clear of debris using cleaning equipment so that loose material does not become a projectile and enter an engine duct (see foreign object damage). In adverse weather conditions, ice and snow clearing equipment can be used to improve traction on the landing strip. For waiting aircraft, equipment is used to spray special deicing fluids on the wings.
Is there an answer to this question: For what kind of aircraft is deicing fluid sprayed on the airfield?

Answer: unanswerable


Question: Shell's primary business is the management of a vertically integrated oil company. The development of technical and commercial expertise in all stages of this vertical integration, from the initial search for oil (exploration) through its harvesting (production), transportation, refining and finally trading and marketing established the core competencies on which the company was founded. Similar competencies were required for natural gas, which has become one of the most important businesses in which Shell is involved, and which contributes a significant proportion of the company's profits. While the vertically integrated business model provided significant economies of scale and barriers to entry, each business now seeks to be a self-supporting unit without subsidies from other parts of the company.
Is there an answer to this question: What is Shell's primary business?

Answer: the management of a vertically integrated oil company


Question: Chen states that the fourth Dalai Lama Yonten Gyatso was granted the title "Master of Vajradhara" and an official seal by the Wanli Emperor in 1616. This was noted in the Biography of the Fourth Dalai Lama, which stated that one Soinam Lozui delivered the seal of the Emperor to the Dalai Lama. The Wanli Emperor had invited Yonten Gyatso to Beijing in 1616, but just like his predecessor he died before being able to make the journey.
Is there an answer to this question: Why didn't Yonten Gyatso make it to Beijing?

Answer: he died


Question: The southwest of the country is a coastal plain for which the primary drainage is the Kouilou-Niari River; the interior of the country consists of a central plateau between two basins to the south and north. Forests are under increasing exploitation pressure.
Is there an answer to this question: What kind of geography does the northeast of the country have?

Answer:
unanswerable