Question: In the west, the Russians were dissuaded from attacking Vidin by the presence of the Austrian forces, which had swelled to 280,000 men. On 28 May 1854 a protocol of the Vienna Conference was signed by Austria and Russia. One of the aims of the Russian advance had been to encourage the Orthodox Christian Serbs and Bulgarians living under Ottoman rule to rebel. However, when the Russian troops actually crossed the River Pruth into Moldavia, the Orthodox Christians still showed no interest in rising up against the Turks.:131, 137 Adding to the worries of Nicholas I was the concern that Austria would enter the war against the Russians and attack his armies on the western flank. Indeed, after attempting to mediate a peaceful settlement between Russia and Turkey, the Austrians entered the war on the side of Turkey with an attack against the Russians in the Principalities which threatened to cut off the Russian supply lines. Accordingly, the Russians were forced to raise the siege of Silistra on 23 June 1854, and begin abandoning the Principalities.:185 The lifting of the siege reduced the threat of a Russian advance into Bulgaria.
Is there an answer to this question: What river did the Russians crossed when they entered the city of Moldavia?

Answer: River Pruth

Question: The defence estate is divided as training areas & ranges (84.0%), research & development (5.4%), airfields (3.4%), barracks & camps (2.5%), storage & supply depots (1.6%), and other (3.0%). These are largely managed by the Defence Infrastructure Organisation.
Is there an answer to this question: What percentage of barracks & camps are managed by airfields?

Answer: unanswerable

Question: Of the third Dalai Lama, China Daily states that the "Ming dynasty showed him special favor by allowing him to pay tribute." China Daily then says that Sonam Gyatso was granted the title Dorjichang or Vajradhara Dalai Lama in 1587 [sic!], but China Daily does not mention who granted him the title. Without mentioning the role of the Mongols, China Daily states that it was the successive Qing dynasty which established the title of Dalai Lama and his power in Tibet: "In 1653, the Qing emperor granted an honorific title to the fifth Dalai Lama and then did the same for the fifth Panchen Lama in 1713, officially establishing the titles of the Dalai Lama and the Panchen Erdeni, and their political and religious status in Tibet."
Is there an answer to this question: What was the the third Dalai Lama allowed to do?

Answer: pay tribute

Question: In the Middle Ages, several powerful Somali empires dominated the regional trade including the Ajuran Sultanate, which excelled in hydraulic engineering and fortress building, the Sultanate of Adal, whose general Ahmad ibn Ibrahim al-Ghazi (Ahmed Gurey) was the first commander to use cannon warfare on the continent during Adal's conquest of the Ethiopian Empire, and the Sultanate of the Geledi, whose military dominance forced governors of the Omani empire north of the city of Lamu to pay tribute to the Somali Sultan Ahmed Yusuf.
Is there an answer to this question: What Somali leader received tribute from the Omani empire?

Answer:
Sultan Ahmed Yusuf