| Rocks which have solidified directly
from molten materials are called igneous rocks. Igneous rocks are commonly
referred to as primary rocks because they are the original source of material
found in sedimentaries and metamorphics. Igneous rocks compose the greater part
of the earth’s crust, but they are generally covered at the surface by a
relatively thin layer of sedimentary or metamorphic rocks. Igneous rocks are
distinguished by the following characteristics: (1) they contain no fossils; (2)
they have no regular arrangement of layers; and (3) they are nearly always made
up of crystals. Sedimentary rocks are composed largely of minute fragments derived from the disintegration of existing rocks and in some instances from the remains of animals. As sediments are transported, individual fragments are assorted according to size. Distinct layers of such sed A. Granite. B. Shale. C. Slate. D. Limestone. [单项选择]Natural foods also include animals which have been allowed to feed and move freely in healthy pastures.（）
A. 自然食品还有动物，这些动物可以允许被自由喂养。 B. 自然食品还包括在牧地上自由吃食和自由活动的动物。 C. 自然食品还有动物，这些动物可以在健康牧地上吃食和自由活动。 D. 自然食品还包括允许在健康牧地上吃食和自由活动的动物。 E. 自然食品还包括在牧地上吃食和自由活动的健康的动物。 [单项选择]Rocks which have solidified directly from molten materials are called igneous rocks. Igneous rocks are commonly referred to as primary rocks because they are the original source of material found in sedimentaries and metamorphics. Igneous rocks compose the greater part of the earth’s crust, but they are generally covered at the surface by a relatively thin layer of sedimentary or metamorphic rocks. Igneous rocks are distinguished by the following characteristics: (1) they contain no fossils; (2) they have no regular arrangement of layers; and (3) they are nearly always made up of crystals.
Sedimentary rocks are composed largely of minute fragments derived from the disintegration of existing rocks and in some instances from the remains of animals. As sediments are transported, individual fragments are assorted according to size. Distinct layers of such sediments as gravels, sand, and clay build up, as they are deposited by water and occasionally wind. These sediments vary in size wit A. Granite. B. Shale. C. Slate. D. Limeston [简答题]Electronic computers, which have many advantages, cannot carry out creative work and replace man.
[单项选择]If x+3y=3 and (x+y)2=4, which of the following is a possible value of x
A. -8 B. -5 C. 5 [单项选择]The goods which have entered the territory, approved by the Customs as items for which no formalitied are preformed in the way of duty payment, and will be reshipped out of the territory after being stored, processed or assembled in the territory are defined as（）
A. bonded goods B. through goods C. transshipment goods D. transit goods 我来回答: 提交
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