A
the identification and location of the damage.
B
the movement of some points.
C
the renounce of the bridge.
D
the distribution of the energy.
Questions 10-13
Choose NO MORE THAN THREE WORDS from the passages for each answer.
10
The weight of the 2500 bridges is sustained by
……………….in every sector.
11
……………….. were set up by the Los Alamos team in order to test the movement of
the bridge.
12
In order to cause break, the Los Alamos team decided to make a
………………… at first
step.
13
The
……………………….. in the bottom of the bridge resembles "I"shape.
DAY 19
READING PASSAGE 2
You should spend about 20 minutes on Questions 1-16, which are based on Reading
Passage 1 below
The shape of bird eggs
A
A sandpiper’s egg is shaped like a teardrop, an owl’s looks a bit like a golf ball, and
a hummingbird’s resembles a tiny bean. Now, for the first time, scientists in the US have
come up with a convincing explanation for this variation. Princeton University evolutionary
biologist Mary Stoddard has long been fascinated by the fact that eggs are so diverse in
shape even though they all basically serve one function: nourish and protect the
developing chick inside. She recently headed and interdisciplinary team of evolutionary
biologists, computer scientists, mathematicians and physicists, with the expectation of
bringing together different ways of looking at bird egg shapes and achieving a better
understanding of them.
B
Fortunately, over the past century, the Museum of Vertebrate Zoology at the
University of California, Berkeley has amassed thousands of egg shells from 1,400
species, representing about 14% of all birds, and put digital photos of them online. Using
this database, Stoddard and her team at Princeton University wrote a computer program,
which they called Eggxtractor, that can select the image of any egg and calculate it length,
width and shape. The team used these calculations to determine how far from perfectly
spherical each of nearly 50,000 eggs in their sample was
– that is, how pointed or
elongated each was.
C
Next, the research team attempted to answer how and why eggs might have
acquired these varying shapes. Rather than looking at the outer hard shell, as one might
expect, the researchers conc
entrated on the egg’s soft thin inner membrane, which is, in
fact, essential in fixing the egg’s shape. Stoddard worked with Harvard University physicist
L.Mahadevan and Ee Hou Yong of China’s Nanyang Technological University to devise a
mathematical repre
sentation based on the membrane’s properties and how much pressure
it received from the unhatched chick within the egg. They then used their model to create
many different egg shapes by altering the membrane’s stiffness and changing the
pressure. ‘Adjusting these [features] allows us to generate the entire diversity of egg
shapes that we observe in nature,’ Stoddard says.
D
When Stoddard and her colleagues made a diagram showing the relationship
between some 1,000 bird species, they realized that members of each closely associated
species tended to lay eggs with the same characteristic shape. The researchers then
investigated why egg shapes might be so spectacularly diverse. Some scientists had
previously believed that the shape might depend on nest location: cliff-nesting birds, it was
thought, lay pointed eggs so that if the eggs are knocked, they spin in a circle rather than
rolling of the cliff. Other scientists suggested that birds lay eggs in shapes that pack
together most economically in a nest. Stoddard and her researchers found neither of these
hypotheses to be persuasive.
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