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Cracking the toefl ibt 2008 part 37

In a living creature, different sequences of DNAr instruct cells to create certain proteins. In one of the Avida creations, different sequences of computer code instruct the program to perform certain functions. In Doih cases, the reproduction of the organisms is subject to forces such as compaction and mutation. | íJan -l I .if- used an enamel-coated iron plate. Ferrotypes became popular with photographers who set up stalls at street fairs and inexpensive resorts because ftrisi could be exposed and developed very quickly. Iron plates were also much less expensive than copper plates arid the resulting photographs were less fragile than daguerreotypes. On the other hand iron unlike copper could rust if not properly stored. Many old ferrotypes were destroyed by long-term display in hot and moist environments. THE PRINCETON REVIEW TOEFL ÍBT PRACTICE TEST 385 13. Which of the following can be inferred from paragraph 1 of the passage A B C D Some photographs are called daguerreotypes inaccurately. Daguerreotypes were popular for most of the 1800s. Not all daguerreotypes were made by technicians. Tintypes and ferrotypes were the first kinds of photographs. Paragraph 1 is marked with an arrow Daguerreotypes - Only a small number of professional photographers ever had any practical experience as daguerreotypists those technicians who made photographs through the daguerreotype process. By strictest definition the daguerreotype process was common for 20 years in the mid-t800s. Other ways ot making photographic images on metal plates such as tintypes and ferrotypes were developed rapidly after the advent of the daguerreotype. They quickly eclipsed it in popularity. Today the surviving photographs produced by these methods are often referred to as daguerreotypes but that designation is incorrect. It is not surprising that photography enthusiasts began looking tor alternatives to the daguerreotype almost immediately. The materials it required were both expensive the plates contained silver and one of the developing solutions contained gold and extremely risky. Strict poisoning by noxious gases. The steps involved in preparing and exposing a daguerreotype were as laborious and frustrating as they were hazardous images were recorded on copper plates Io which several thin coats ot silver had