Nathan, five years old, has grown very curious about all the things around him. He asks his mom, “Why is the sky blue? Why is the grass green? Why does granddaddy have hair on his face?” Nathan is also using his newly emerged reasoning skills. His reasoning skills prompt him to try to understand why things are the way they are. Nathan is in which of Piaget’s stages?  

You may use the following tables to answer questions involving the Normal curve. Normal Curve Tables

The amount of time required for each of 100 mice to navigate through a maze was recorded.  The histogram below shows the distribution of times, in seconds, for the 100 mice.   Which of the following values is the best estimate of the standard deviation of the 100 times?

A survey of a large college class asked four questions.  Each histogram below summarizes the student responses to one of the questions. Match each histogram to its corresponding survey question.

The smoothed histograms below show the distributions of Creativity scores for two groups of students.  Creativity was measured on a 25-point scale ranging from 1 to 25, with higher scores indicating greater Creativity. Approximately, what percent of the students in Group A scored below the median of Group B?

A student obtains a raw score of 23 in a moderately skewed (asymmetrical) distribution of test scores with a median of 23.  What would be the student’s score in standard units (z-score)?

The distribution of zucchini weights is approximately Normal with a mean of  pounds and a standard deviation of  pounds.  Which of the following shaded regions best represents the probability that a randomly selected zucchini weighs between 0.55 and 1.3 pounds?

The weights of bars of Dove Body Soap are approximately Normally distributed with a mean of 100 grams (g) and a standard deviation of 20 g.   Which of the following intervals of weights will contain the largest percentage of bars in the distribution of weights?

Which resonance form is likely to contribute most to the correct structure of OCN-?

Determine the hybridization of the carbons labeled 2 and 6.