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:

Equilibrium Rate

The balance point in financial markets or for specific financial instruments, where supply meets demand.

Marginal Workers

Individuals who are employed in a job that does not fully utilize their skills or capabilities, often due to economic fluctuations or lack of available positions.

Real Wages

Wages adjusted for inflation, representing the true purchasing power of income earned from labor.

Productivity

A measure of the efficiency of production, often evaluated as the ratio of output to input in the production process.