What is the value of x?

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

All per-unit concepts rely on ratios, meaning, to provide a type of measurement

The lengths of nails produced in a factory are normally distributed with a mean of 4.91 centimeters and a standard deviation of 0.05 centimeters. find the two lengths that separate the top 4% and the bottom 4%. these lengths could serve as limits used to identify which nails should be rejected. round your answer to the nearest hundredth, if necessary.