What is the probability that a ramdomly selected, normally distributed value lies below one standard deviation from the mean?

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

Will gve pints stars and brainliest

Find the area of the triangle shown 3 by 6