Comparison of the growth rings of ancient trees enables scientists& a- A: Q% r6 Y+ ^' r
to determine from a piece of timber the year in which the tree used
( J# p& F* Y' i6 w" n8 Xfor the timber was felled. Hence, by analyzing the growth rings in % p: G; h; y- c' i/ s0 s: |- Q
timber surviving from ancient buildings, archaeologists can deter-
' `' z8 K S+ D7 W" `2 h) umine precisely when those buildings were constructed.
! F* y' F5 L% ?- S Which of the following is an assumption on which the argument - t5 @6 F: }" e! H, j$ Z1 X9 p
depends?9 Z |1 W. _, K% X: i" X1 o
The timber used for construction purposes in ancient times
j; Q7 x$ M1 R# c was made from very old trees. # Z' ^+ \6 P/ C$ V
The timber that was used in ancient building construction had
) u3 ]% }# |: Y" k4 q2 U/ c not, prior to being used in the construction of the buildings,/ x. Y8 Q0 O3 p" \
lain unused for an indeterminable amount of time. , A$ U* F6 f/ j9 p4 _: V2 Y
The growth rings of any tree felled in a given year are iden-2 ]5 H1 U, ?- W+ u+ h
tical to the growth rings of any other tree felled in that year. 8 o( z s. P% t+ n6 v- N
The oldest of the ancient buildings that survive to the present
w4 s5 E a/ A" X$ H! e day were constructed of the most durable woods.
+ [: Y9 b0 s' Z( J9 Q u Ancient builders did not use more than one type of wood for
) ^# Y3 Z* N6 {5 c the construction of a given building.
. H* K* Q" N7 F答案：A |
发表于 2012-8-15 12:40:43
