L3：
Lecture 3
第一题
What is the lecture mainly about?
AThe manufacturing of glass by early humans
BHow crystal patterns develop within silicate glass
CWays in which different types of natural glass are formed
DA study of diatoms found in volcanic glass
第二题
In what way does the professor help students visualize the atomic structure of glass? ABy encouraging them to think about windowpanes and optical fibers
BBy instructing them to look at drawings of atoms online
CBy comparing atoms to groups of people
DBy presenting the results of a chemistry experiment
第三题
What property of lava does the professor focus on?
AThe amount of it produced during a typical volcanic eruption
BThe type of rock it was before it melted
CThe temperature at which it melts sand
DThe speed at which it solidifies
第四题
What points does the professor make about obsidian? Select 2 answers
AIt can be used to darken window glass.
BDecorative objects are created from it.
CIt has sometimes been used as a form of money.
DIt was made into cutting tools.
第五题
Why does the professor encourage students to view a video of diatoms?
ATo compare their size with grains of sand
BTo appreciate their beauty and variety
CTo see the process by which diatoms extract silicon from water
DTo see the difference between diatom glass and volcanic glass
第六题
What does the professor mean when he says this
AThe student should research the answer on his own.
BThe student should talk to him after class.
CThe process is not fully understood.
DIt would take a team of experts to answer the student’s question.
