Table 75
the Following Results Were Obtained from a Use-Dilution Test

question 5

Short Answer

Table 7.5
The following results were obtained from a use-dilution test of two disinfectants. Cultures were inoculated into tubes containing varying concentrations of the disinfectants, incubated for 10 min. at 20°C, and then transferred to growth media without disinfectant. (+ = growth; - = no growth)
$\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\text { Disinfectant A }$
$\begin{array}{rcc}\text { Concentration } & \text { Gram-positive bacteria } & \text { Gram-negative bacteria } \\1: 10 & - & - \\1: 20-70 & - & + \\1: 80 & + & + \\1: 90 & + & + \\1: 100 & + & + \\1: 110-500 & + & +\end{array}$

$\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\text { Disinfectant B }$
$\begin{array}{rcc}\text { Concentration } & \text { Gram-positive bacteria } & \text { Gram-negative bacteria } \\1: 10 & - & - \\1: 20-70 & + & + \\1: 80 & + & + \\1: 90 & + & + \\1: 100 & + & + \\1: 110-500 & + & +\end{array}$ In Table 7.5, which disinfectant is most effective? Against which group of bacteria is Disinfectant A most effective?

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Definitions:

Predetermined Overhead Rate

A rate used to apply manufacturing overhead to products or job orders, based on a predetermined formula.

Work in Process

Inventory that includes partially completed goods that are still undergoing manufacturing or production processes.

Cost of Goods Sold

The total cost associated with producing the goods sold by a business, including materials, labor, and manufacturing overhead.

Direct Labour-hours

The total number of hours worked by employees directly involved in the production process.