Mary and Debra Stand on a Snow-Covered Roof

question 79

Multiple Choice

Mary and Debra stand on a snow-covered roof. They both throw snowballs with the same initial speed, but in different directions. Mary throws her snowball downward, at 30° below the horizontal; Debra throws her snowball upward, at 30°. When the snowballs reach the ground below,

• A) Debra's snowball will stay in the air longer than Mary's.
• B) Mary's snowball will stay in the air longer than Debra's.
• C) Both snowballs will take the same amount of time to hit the ground.
• D) Debra's snowball never hits the ground since it is thrown upwards.
• E) Mary's snowball never hits the ground since it is thrown downwards.

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Definitions:

T-test

A statistical test used to compare the means of two groups.

Null Hypothesis

A statement in statistics that proposes there is no significance difference or effect, generally serving as the default or starting assumption in hypothesis testing.

Alpha

The threshold for significance in statistical testing, typically set at 0.05, below which the null hypothesis is rejected.

T-test

A statistical test used to compare the means of two groups, often employed to determine if there are significant differences between them.