Does the sentence "Nevertheless, his son, Henry Babbage, completed a simplified version of the analytical engine's computing unit (the mill) in 1888." provide a valid answer to the question "Who was Charles Babbage's son?" OPTIONS:
- yes
- no

A: yes

Does the sentence "Mathematical and logical propositions (e.g. "that the square of the hypotenuse is equal to the sum of the squares of the two sides") are examples of the first, while propositions involving some contingent observation of the world (e.g. "the sun rises in the East") are examples of the second." provide a valid answer to the question "What type of human knowledge is "the sun rises in the East"?" OPTIONS:
- yes
- no

A: no

Does the sentence "The only extant ice sheets are the two that cover most of Antarctica and Greenland." provide a valid answer to the question "How many extant ice sheets exist?" OPTIONS:
- yes
- no

A: yes

Does the sentence "The history of ecology in the 20th century is closely tied to that of environmentalism; the Gaia hypothesis, first formulated in the 1960s, and spreading in the 1970s, and more recently the scientific-religious movement of Deep Ecology have brought the two closer together." provide a valid answer to the question "When was the Gaia hypothesis discovered?" OPTIONS:
- yes
- no

A:
yes