Correct Answer: C

Rationale: The correct answer is C: Bell-shaped. A symmetric distribution with a single peak is characteristic of a bell-shaped distribution, also known as a normal distribution. This distribution forms a symmetrical, bell-like curve when graphed. Choice A, 'Uniform,' would describe a distribution where all values have equal probability. Choice B, 'Bimodal,' would indicate a distribution with two distinct peaks. Choice D, 'Skewed right,' suggests a distribution where the tail on the right side is longer or more pronounced, unlike the symmetrical bell-shaped distribution described in the question.

Correct Answer: D

Rationale: To calculate a 10% tip on a bill of $28.40, you would first find 10% of $28.40, which is $2.84. Since you typically round up when leaving a tip, the estimated gratuity would be $3.00. Option A is incorrect as it is too high for a 10% tip. Option B is incorrect as it is too high. Option C is incorrect as it is too low for a 10% tip. Therefore, the correct answer is $3.00.

Correct Answer: D

Rationale: To find the cost of one syringe, divide the total cost by the number of syringes: $660.00 · 55 = $12. Therefore, the cost of four syringes is 4 x $12 = $48. Choices A, B, and C are incorrect because they do not correctly calculate the cost per syringe or the total cost of four syringes.

Correct Answer: A

Rationale: To convert Fahrenheit to Celsius, you start by subtracting 32 from the Fahrenheit temperature and then divide the result by 1.8. This formula accounts for the freezing point of water at 32°F and the conversion factor to Celsius. To convert Celsius to Fahrenheit, you multiply the Celsius temperature by 1.8 and then add 32. This process takes into consideration the conversion factor from Celsius to Fahrenheit and the freezing point of water. Choice B is incorrect as dividing by 2 instead of 1.8 would yield an inaccurate conversion. Choice C is incorrect as it involves incorrect operations for both conversions. Choice D is incorrect as subtracting 30 instead of 32 for Fahrenheit to Celsius and multiplying by 2 instead of 1.8 for Celsius to Fahrenheit would provide incorrect results.

Correct Answer: D

Rationale: The scatter plot illustrates the relationship between students' exam scores and heights. There is no correlation between these variables, as height is not expected to have a direct impact on exam scores. Therefore, choice D, 'No correlation,' is the correct answer. Choices A, 'Positive,' and C, 'Negative,' are incorrect because the scatter plot does not indicate a positive or negative correlation between exam scores and heights. Choice B, 'Positive and Negative,' is also incorrect because the scatter plot does not exhibit both positive and negative correlations simultaneously.