input: 2017 South Sudan famine

Since the early months of 2017, parts of South Sudan have been experiencing a famine following several years of instability in the country's food supply caused by war and drought. The famine, largely focused in the northern part of the country, has been estimated to affect almost five million people (about 50% of the South Sudanese population), with food shortages expected to spread by the middle of the year.
was drought an important cause of the recent famine in south sudan
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output: yes

input: Negative-calorie food

Foods that are claimed to be negative in calories are mostly low-calorie fruits and vegetables such as celery, grapefruit, lemon, lime, apple, lettuce, broccoli, and cabbage. There is no scientific evidence to show that any of these foods have a negative calorific impact. Celery has a thermic effect of around 8%, much less than the 100% or more required for a food to have ''negative calories''. A stalk of celery provides 6 calories to the body, but the body expends only half of a calorie digesting it. Even proteins, which require the most energy to digest, have a thermic energy of only 20%--30%.
is it true that celery has negative calories
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output: no

input: Properties of metals, metalloids and nonmetals

Metals comprise the large majority of the elements, and can be subdivided into several different categories. From left to right in the periodic table, these categories include the highly reactive alkali metals; the less reactive alkaline earth metals, lanthanides and radioactive actinides; the archetypal transition metals, and the physically and chemically weak post-transition metals. Specialized subcategories such as the refractory metals and the noble metals also exist.
are there more metallic elements than non metallic elements
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output: yes

input: Shallot

Its close relatives include the garlic, leek, chive, and Chinese onion.
is a shallot the same as a leek
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output:
no