Self-study
Early pencil leads were made of solid graphite mined in Cumberland, in Britain. ██████ ███████ ██ █████████████ ██████ █████ ████ ████████ ████████ ███ ███ ██████ ██ ████████ █████████ ██ ███ ██████████ ██ ██████ ██ ███ ██████ ████ ██████ ███ ██ ███ ████ ███████ ███ ████ ███ ██ ██████ ██ ██████████ █████████
Summary
Early pencil leads were made from solid graphite mined in Cumberland, in Britain. Modern pencil leads are manufactured from powdered graphite. Powdered graphite was made possible from research sponsored by the French government in the 1790s. During that time period, France was at war with Britain and had no access to solid graphite from Cumberland.
Strongly Supported Conclusions
The stimulus supports the conclusion that in the 1790s, France could not easily replace Cumberland graphite by sourcing pencil leads from another source of solid graphite. It also supports the conclusion that the war between France and Britain in the 1790s restricted trade between the two countries.
9.
The information above most strongly ████████ █████ ███ ██ ███ ██████████
a
The world's only ███████ ██ ████████ ████████ ███ ███████████ ██ ███████ ██ ██ ███████████ ██ ████████
This answer is unsupported. To say that solid graphite for pencil lead is “only” found in Cumberland is too strong. We only know from the stimulus that France could not easily switch to another source, but there could be many reasons for that, even if other sources exist.
b
In the 1790s, ████████ ██████████ ███ ███ ████ ██ ███ ██████████ ██████ ██ █████ ████████ ███████████ ██ ████ ████████ ████ ███ ████████
This answer is strongly supported. When France did not have access to Cumberland graphite mined, they sponsored research to develop powdered graphite because they must not have been aware of any other accessible source of solid graphite. If they could have sourced solid graphite from elsewhere, there would be no need to research new manufacturing methods.
c
One of the ██████ ██ ███ ███████ ██████ ███ ███████ ██ ███ █████ ███ ███ ███████ ████████████ ███████ ██ █████ ███ ██████ ██ ██████████ ████████ █████ ████████ ██ ███████
This answer is unsupported. We don’t know anything about what caused the war between France and Britain from the stimulus.
d
Government-sponsored research frequently █████ ████ ██ ██████████ ████ ███ ██ █████ ███████ ██ ████████
This answer is unsupported. To say that this research “frequently” results in inventions is too strong. We only know of one example, powered graphite, from the stimulus.
e
Even today, all ██████ █████ ███████ ██████████ █████████
This answer is unsupported. We don’t know anything about what modern pencil leads contain from the stimulus. We only know that modern methods of manufacturing involve powered graphite.