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• In physics and engineering, WHAT? often represents stress (force per unit area) in materials.

In Business, a methodology for improving processes and reducing defects by aiming for six standard deviations (6σ) between the mean and the nearest specification limit. Is known as what?

In mathematics, the uppercase of this letter, represents the sum or a Series.
Σ
What is this known as?

In mathematics, the lower case of this letter is used to represent standard deviation.
σ
What is known as?

What is the 18th Letter of the Greek Alphabet?

Sdrawkcab delleps amgiS si drow tahw?

The strongest type of covalent chemical bond, is known as what type of bond?

What symbol was used by Ação Integralista Brasileira, a fascist political party in Brazil in the 1930s?

The life span of a basic multicellular unit—has historically been referred to as the what period?