Construya la tabla de verdad para cada una de las siguientes proposiciones e identifica si es una tautología, contradicción y contingencia. a) ( ) ∨ (¬ ∨ )

b) ¬ ( ) ∨ ¬ ( ∨ )

c) ( ¬) ∨ ¬ ( ¬)

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

What is the best approximation for the area of a circle with a radius of 4 m ? use 3.14 to approximate pi

1. how do you convert the repeating, nonterminating decimal 0. to a fraction? explain the process as you solve the problem.