定位就是（）零件在空间的位置或零件见的相对位置。

下列各图与相应描述不相符的是

A．足球被守门员接住过程中，球的运动状态改变

B．乒乓球在空中向前飞行时不受到球拍的作用力

C．冰壶被发出后前进过程中受到重力和摩擦力两个力的作用

D．垒球被抛出在空中飞行时由于空气的阻力，球的机械能减少

距离保护安装处分支与短路点所在分支连接处还有其他分支电源时，流经故障线路的电流，大于流过保护安装处的电流，其增加部分称之为汲出电流。

痹病的共同特征是（）。

A.肢体沉重

B.肢体关节灼热

C.肢体关节疼痛，曲伸不利

D.肌肤麻木

E.以上都不是

Film Exchanges in America’s Early Movie Industry

Motion pictures were exhibited to the public in the late 1800s, though the first device to accomplish this would seem very unfamiliar to today’s movie-going audiences. Thomas Edison’s 1893 Kinetoscope was little more than a wooden box with a small glass window. Intended only for individual viewing, it housed a roll of film, a mechanical device to circulate the film, and a small light to illuminate it. A person would peer through the window and watch a short moving sequence, usually just a depiction of an everyday
event or the performance of an acrobat or dancer. Needless to say, the medium’s ability to serve only one customer at a time severely limited its profitability.
Everything changed two years later with the advent of projection, by which a much larger film image could be shown to multiple viewers simultaneously. The Lumiere brothers of France were the first to introduce this new technology with a projection machine called a cinematograph. Edison was quick to follow their lead and created his Vitascope projector in late 1895. With the potential to make money by charging admission to movies now within reach, the innovators of the film industry were ready to expand their business ventures.
There were two industry models in practice during the early 1900s. A handful of successful firms, such as the Biograph Company, owned the equipment to make their own films as well as the venues in which to display them. Such companies were rare, however; most films were shown by independent exhibitors. These included traditional theater owners, who added short film presentations to their programs of live-action entertainment, and traveling cinema exhibitors, who moved from town to town to reach new audiences, often following

circuits

established by rural fairs. They typically purchased films directly from the production companies that made them, paying a set price per foot of film regardless of its content. Because movies of the time were never longer than one or two minutes, it was feasible to buy them outright.

However, this system failed to attract significant audiences as the public soon tired of the small stock of films exhibitors had to offer, and the reels of film themselves deteriorated quickly through repeated transport and screening in traveling cinema shows.

Things changed again when producers began increasing the length of their films in order to tell more complex stories. Longer films entailed higher prices, and it became difficult for small-scale exhibitors to purchase them. This, in turn, prevented production studios from creating as many movies as they could, since they had no one to sell them to. It was precisely this dilemma that gave rise to the film exchange. An early version of a motion-picture distributor, film exchanges were responsible for bridging the gap between production and exhibition. They financed production studios, giving them the funds they needed to film more movies. Then, they purchased these films and rented them out to exhibitors around the country for a fraction of what it would have cost the exhibitors to purchase the films themselves.
The film-exchange system revolutionized the industry, greatly benefiting all parties involved.

Film rentals allowed exhibitors to show a wide variety of movies and gave them constant access to new films so they could change their programs frequently.

This led to the rise of what we now know as the movie theater, a venue dedicated solely to the public exhibition of films.

Film exchanges made money by taking a percentage of ticket sales, and the production studios were paid by the exchanges.

Moreover, as a result of the increase in revenue that came as movies gained popularity, the studios began to focus on elevating the quality of their products.
Many historians view the development of film exchanges as the single most important factor in the transformation of the film industry from an entertainment novelty to a major business. After 1920, independent exchanges grew scarcer as a few corporations succeeded in capturing control of the production, distribution, and exhibition of films. Yet many of the practices established by film exchanges prior to the 1920s are still used today by the most successful Hollywood distributors.

What can be inferred from paragraph 4 about film exchanges

A. They charged high rental prices for the films they owned.
B. They possessed large amounts of startup capital.
C. They participated in both production and exhibition.
D. They broadened the market for films overseas.

以下说法中，错误的是 ( )

A．收盘价高于开盘价时为阳线

B．收盘价高于开盘价时为阴线

C．收盘价低于开盘价时为阴线

D．收盘价高于开盘价时为阳线