In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: What is sometimes combined with an RPG tube to keep from harming the user?, Context: Rocket-propelled grenades can be—and often are—used against hovering helicopters (e.g., by Somali militiamen during the Battle of Mogadishu (1993)). Firing an RPG at steep angles poses a danger to the user, because the backblast from firing reflects off the ground. In Somalia, militia members sometimes welded a steel plate in the exhaust end of an RPG's tube to deflect pressure away from the shooter when shooting up at US helicopters. RPGs are used in this role only when more effective weapons are not available.

Answer: a steel plate in the exhaust end


Question: Who proposed that biological measure should be developed and used?, Context: In the paper "Who's Gay? Does It Matter?", Ritch Savin-Williams proposes two different approaches to assessing sexual orientation until well positioned and psychometrically sound and tested definitions are developed that would allow research to reliably identify the prevalence, causes, and consequences of homosexuality. He first suggests that greater priority should be given to sexual arousal and attraction over behaviour and identity because it is less prone to self- and other-deception, social conditions and variable meanings. To measure attraction and arousal he proposed that biological measures should be developed and used. There are numerous biological/physiological measures that exist that can measure sexual orientation such as sexual arousal, brain scans, eye tracking, body odour preference, and anatomical variations such as digit-length ratio and right or left handedness. Secondly, Savin-Williams suggests that researchers should forsake the general notion of sexual orientation altogether and assess only those components that are relevant for the research question being investigated. For example:

Answer: Ritch Savin-Williams


Question: Who was invited to partake in the event?, Context: Hong Kong: The event was held in Hong Kong on May 2. In the ceremony held at the Hong Kong Cultural Centre in Tsim Sha Tsui, Chief Executive Donald Tsang handed the torch to the first torchbearer, Olympic medalist Lee Lai Shan. The torch relay then traveled through Nathan Road, Lantau Link, Sha Tin (crossed Shing Mun River via a dragon boat, which had been never used before in the history of Olympic torch relays), Victoria Harbour (crossed by Tin Hau, a VIP vessel managed by the Marine Department) before ending in Golden Bauhinia Square in Wan Chai. A total of 120 torchbearers were selected to participate in the event consisting of celebrities, athletes and pro-Beijing camp politicians. No politicians from the pro-democracy camp were selected as torchbearers. One torchbearer could not participate due to flight delay. It was estimated that more than 200,000 spectators came out and watched the relay. Many enthusiastic supporters wore red shirts and waved large Chinese flags. According to Hong Kong Chief Secretary for Administration Henry Tang, 3,000 police were deployed to ensure order.

Answer:
A total of 120 torchbearers