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Analyze the following statements regarding the word ringmaster used in the final paragraph and mark T (True) or F (False):
( ) In literal terms, a ringmaster is the person in charge of a circus performance, especially the one who introduces the acts, guides the audience's attention, and keeps the show moving in the ring.
( ) In the text, the word is used metaphorically.
( ) The "ringmaster" stands for P.T. Barnum as the director/controller of attention and spectacle, the one who teaches people that any kind of publicity (even fake or sensational) is acceptable as long as it grabs notice.
( ) "Ringmaster", in popular culture, means the master-of-ceremonies of a showy, attention-driven culture, not just a literal circus host.
Which alternative CORRECTLY fills in the parentheses a bove?
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According to the passage, what is the main criticism the author has about the idea that any publicity is good publicity?
Em um manual de operação de um sistema de espectrometria de massas (EM) com fonte de ionização por electrospray (ESI), está indicado o seguinte procedimento:

"To ensure optimal ionization of biomolecules, use a capillary voltage between 3.5 and 4.5kV. The nebulizer gas should be set at 50 psi, and the drying gas should be heated to 350°C. Maintain a source temperature of 120°C. For larger molecules, increasing the capillary voltage to 5kV may improve ionization efficiency."

Com base nas informações fornecidas, a recomendação sobre o ajuste da tensão do capilar é:
Um manual técnico de um sistema de Cromatografia Líquida de Alta Eficiência (CLAE) descreve o ajuste do detector UV-Vis. A seção referente à configuração do comprimento de onda de detecção apresenta a seguinte recomendação:

"For optimal detection of compounds absorbing in the 200 - 300 nm range, set the wavelength between 220 - 230 nm  . For compounds with stronger absorbance above 300 nm, use wavelengths around 280 - 290 nm. Adjust the wavelength to maximize the signal intensity while avoiding excessive noise."

Com base no trecho citado, a instrução CORRETA para o ajuste do comprimento de onda em CLAE é:

Choose the connector that best completes the sentence:


"He studied hard for the exam; ___, he did not achieve the expected results."