A Music Professor Offers His 40 Students the Option of Coming

question 5

Multiple Choice

A music professor offers his 40 students the option of coming to an additional rehearsal session the week before their juries (musical final exams.) In order to decide whether these extra sessions actually help students, he keeps track of who attends them and compares their jury scores to those of students who did not schedule extra sessions.
This study is a(n) :

• A) observational study.
• B) nonrandomized experiment.
• C) completely randomized experiment.
• D) randomized block design.
• E) matched pairs design.

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Definitions:

Hornfels

A fine-grained metamorphic rock formed by the contact metamorphism of shale and other clay-rich rocks.

Foliation

The repetitive layering in metamorphic rocks, which occurs due to the reorientation of minerals under intense heat and pressure.

Thrust Fault

a type of reverse fault where the upper block, above the fault plane, moves up and over the lower block.

Metamorphic Rock

rock that has undergone transformation from an original form due to high pressure, high temperature, or both.