Table 74
the Results Below Were Obtained from a Use-Dilution Test

question 12

Short Answer

Table 7.4
The results below were obtained from a use-dilution test of two disinfectants. Cultures were inoculated into tubes with varying concentrations of disinfectants and incubated for 24 hr at 20°C, then subcultured in nutrient media without disinfectants.(+ = growth; - = no growth)
$\quad\quad\quad\quad\quad\quad\quad\quad\text { Disinfectant } 1$$\quad\quad\quad\quad\quad\text { Disinfectant } 2$
$\begin{array}{rcccc}\text { Concentration } & \text { Initial } & \text { Subculture } & \text { Initial } & \text { Subculture } \\1: 10 & - & + & - & - \\1: 90 & + & + & - & - \\1: 900 & + & + & - & - \\1: 90,000 & + & + & - & - \\1: 900,000 & + & + & - & + \\1: 9,000,000 & + & + & - & +\end{array}$ In Table 7.4, what is the minimal bacteriostatic concentration of each disinfectant? Which compound is bactericidal? At what concentration?

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Definitions:

Social Program

Government initiatives designed to provide support and improve living standards for its citizens, including welfare, healthcare, and education services.

Cost-Benefit Analysis

A systematic approach to evaluate the strengths and weaknesses of alternatives in order to determine the best option through balancing costs and benefits.

Crime-Control Program

Initiatives or strategies designed to reduce crime and improve public safety through various means, including law enforcement and community engagement.

Public Good

Goods that are non-excludable and non-rivalrous, meaning they can be used by everyone and one person's use does not reduce availability to others.