Let x1, x2, and x3 represent the times necessary to perform three successive repair tasks at a certain service facility. suppose they are independent, normal rv's with expected values μ1, μ2, and μ3 and variances σ12, σ22, and σ32, respectively. if μ1=μ2 = μ3=70 and σ1^2=σ2^2=σ3^2=21, calculate p(to < 231) and p(168 < t< 231).

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil

You’re giving a cube with a length of 2.5 cm and a width of 2.5 cm and a high of 2.5 cm you place it on a scale and it is 295 g calculate the density

If my mom gets $13.05 an hour, and she works from 3: 30 to 10: 45 in the morning, how much money does my mom make?