19.The paragraph following the passage most likely discusses

(A)specific double radio sources

(B)an explanation of the synchrotron process

(C)possible reasons for the presence of cosmic jets

(D)the discovery of the first double radio sources.

Questions 20-28

The sculptural legacy that the new United States inherited from its colonial predecessors was far from a rich one,and in fact,in 1776sculpture as an art form was still in the hands of artisans and craftspeople.Stone carvers engraved their motifs of skulls and crossbones and other religious icons of death into the gray slabs that we still see standing today in old burial grounds.Some skilled craftspeople made intricately carved wooden ornamentations for furniture or architectural decorations,while others caved wooden shop signs and ships'figureheads.Although they often achieved expression and formal excellence in their generally primitive style,they remained artisans skilled in the craft of carving and constituted a group distinct from what we normally think of as "sculptors"in today's use of the word.

On the rare occasion when a fine piece of sculpture was desired,Americans turned to foreign sculptors,as in the 1770's when the cities of New York and Charleston,South Carolina,commissioned the Englishman Joseph Wilton to make marble statues of William Pitt.Wilton also made a lead equestrian image of King George III that was created in New York in 1770and torn down by zealous patriots six years later.A few marble memorials with carved busts,urns,or other decorations were produced in England and brought to the colonies to be set in the walls of churches-as in King's Chapel in Boston.But sculpture as a high art,practiced by artists who knew both the artistic theory of their Renaissance-Baroque-Rococo predecessors and the various technical procedures of modeling,casting,and carving rich three-dimensional forms,was not known among Americans in 1776.Indeed,for many years thereafter,the United States had two groups from which to choose -either the local craftspeople or the imported talent of European sculptors.

The eighteenth century was not one in which powered sculptural conceptions were developed.Add to this the timidity with which unschooled artisans -originally trained as stonemasons,carpenters,or cabinetmakers -attacked the medium from which they sculpture made in the United States in the late eighteenth century.

20.What is the main idea of the passage?

(A)There was great demand for the work of eighteenth-century artisans.

(B)Skilled sculptors did not exist in the United States in the 1770's.

(C)Many foreign sculptors worked in the United States after 1776.

(D)American sculptors were hampered by a lack of tools and materials.

21.The word "motifs"in line 3is closest in meaning to

(A)tools

(B)prints

(C)signatures

(D)designs

22.The work of which of the following could be seen in burial grounds?

(A)European sculptors

(B)Carpenters

(C)Stone carves

(D)Cabinetmakers