Before Uncoupling a Tractor from a Semi-Trailer,which of the Following

question 33

Multiple Choice

Before uncoupling a tractor from a semi-trailer,which of the following should be done?

• A) ensure the trailer parking brakes are released
• B) apply the trailer service brakes
• C) lower the trailer dolly legs and raise to take some weight off the tractor
• D) ensure the 5th wheel main and secondary locks are both fully engaged

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Definitions:

Interquartile Range

The difference between the 75th and 25th percentiles of a data set, measuring the spread of the middle 50% of the data.

Summary Statistics

Numeric values that summarize and provide information about your sample data, including measures like mean, median, and standard deviation.

Lower Fence

A term used in descriptive statistics and boxplot construction, referring to a value below which lies an outlier in a dataset, typically calculated as Q1 - 1.5*IQR, where Q1 is the first quartile and IQR is the interquartile range.

Box And Whisker Plot

A graphical representation of data that displays the median, quartiles, and extremes, providing a visual summary of the distribution.