TASK DEFINITION: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
PROBLEM: Why did Cubitt build the new wing?, Context: By 1847, the couple had found the palace too small for court life and their growing family, and consequently the new wing, designed by Edward Blore, was built by Thomas Cubitt, enclosing the central quadrangle. The large East Front, facing The Mall, is today the "public face" of Buckingham Palace, and contains the balcony from which the royal family acknowledge the crowds on momentous occasions and after the annual Trooping the Colour. The ballroom wing and a further suite of state rooms were also built in this period, designed by Nash's student Sir James Pennethorne.

SOLUTION: the couple had found the palace too small for court life and their growing family

PROBLEM: Although Montana is a large state, it has a low what?, Context: Montana i/mntn/ is a state in the Western region of the United States. The state's name is derived from the Spanish word montana (mountain). Montana has several nicknames, although none official, including "Big Sky Country" and "The Treasure State", and slogans that include "Land of the Shining Mountains" and more recently "The Last Best Place". Montana is ranked 4th in size, but 44th in population and 48th in population density of the 50 United States. The western third of Montana contains numerous mountain ranges. Smaller island ranges are found throughout the state. In total, 77 named ranges are part of the Rocky Mountains.

SOLUTION: population

PROBLEM: During which part of the war did the Soviets occupy islands?, Context: At the end of World War II Soviet troops occupied southern Sakhalin Island and the Kuril Islands, making them part of the RSFSR. The status of the southernmost Kurils remains in dispute with Japan.

SOLUTION:
the end