Why Do Stars in the Disk of a Spiral Galaxy

question 11

Multiple Choice

Why do stars in the disk of a spiral galaxy orbit in roughly the same direction, in the same plane in space?

• A)The gas that formed the stars was shaped as a giant, rotating disk.
• B)Collisions between the stars caused their motions to organize into a general, spinning disk direction.
• C)After the stars formed, gravity pulled the stars down into a plane in space, all orbiting a supermassive black hole.
• D)It is pure coincidence; the stars just happen to be going in the same direction.

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Definitions:

DL Wage Variance

The difference between the budgeted wage and the actual wage paid to direct labor employees.

DL Efficiency Variance

The difference between the actual hours worked by direct labor to produce goods and the expected (or standard) hours, multiplied by the standard labor rate.

Skilled Engineering Labor

Workforce with specialized technical and engineering skills, vital for designing, implementing, and maintaining complex systems.

Direct Labor Efficiency Variance

A measure that analyses the variance between the actual hours worked and the standard hours set for producing a certain number of units.