The role of the project manager encompasses many activities including: 1  Planning and Defining Scope. 2  Activity Planning and Sequencing. 3  Resource Planning. 4  Developing Schedules. 5  Time Estimating. 6  Cost Estimating. 7  Developing a Budget. 8  Documentation. 9  Creating Charts and Schedules. 10  Risk Analysis. 11  Managing Risks and Issues.
(Answer #1). The critical angle is the largest angle at which light rays inside a diamond can escape. The more a material bends light, the higher the RI Refractive index, the smaller its critical angle.Because diamond has a high RI, it has only a small critical angle, 24.5 degrees.Answer #1). The critical angle is the largest angle at which light rays inside a diamond can escape. The more a material bends light, the higher the RI Refractive index, the smaller its critical angle.
The reason that diamonds, rubies, sapphires, and emeralds are so prized is largely because they are rare, whereas most semi-precious gemstones are relatively common by comparison. The rarer a gemstone is, the more expensive it tends to be.