In a Controlled Laboratory Environment, a Random Sample of 10

question 7

Multiple Choice

In a controlled laboratory environment, a random sample of 10 adults and a random sample of 10 children were tested by a psychologist to determine the room temperature that each person finds most comfortable. The data are summarized below:

$$\begin{array} { l c c } \hline & \text { Sample Mean } & \text { Sample Variance } \\\hline \text { Adults (1) } & 77.5 ^ { \circ } \mathrm { F } & 4.5 \\\text { Children (2) } & 74.5 ^ { \circ } \mathrm { F } & 2.5 \\\hline\end{array}$$
Suppose that the psychologist decides to construct a 99% confidence interval for the difference in mean comfortable room temperatures instead of proceeding with a test of hypothesis. The 99% confidence interval turns out to be (-2.9, 3.1) . Select the correct statement.

• A) It can be concluded at the 99% confidence level that the true mean comfortable room temperature for children exceeds that for adults.
• B) It can be concluded at the 99% confidence level that the true mean room temperature for adults exceeds that for children.
• C) It can be concluded at the 99% confidence level that the true mean comfortable room temperature is between -2.9 and 3.1.
• D) It cannot be concluded at the 99% confidence level that there is actually a difference between the true mean comfortable room temperatures for the two groups.

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Definitions:

Landscape Features

Physical attributes of the land surface, including mountains, rivers, plains, and valleys.

Pediment

A gently sloping, low-relief plain or erosion surface carved onto bedrock, commonly with a thin, discontinuous veneer of sediment.

Alluvial Fan

A fan-shaped deposit formed where a fast-flowing stream flattens, slows, and spreads typically at the exit of a canyon onto a flatter plain.

Glaciers

Massive, slow-moving rivers of ice that form in regions where snowfall exceeds snowmelt over many years.