Which describes an operating system this is multitasking

Alook-up table used to convert pixel values to output values on a monitor. essentially, all pixels with a value of 190 or above are shown as white (i.e. 255), and all values with a value of 63 or less are shown as black (i.e. 0). in between the pixels are scaled so that a pixel with a value p is converted to a pixel of value 2/127 −+3969). if a pixel has a value of 170 originally, what value will be used to display the pixel on the monitor? if a value of 110 is used to display the pixel on the monitor, what was the original value of the pixel?

Which of these is most responsible for differences between the twentieth century to the twenty-first century?

Helen's credit card has an apr of 15.32% and a grace period of 17 days and helen pays her balance in the full every month. if her last billing cycle ended on september 26, 2009, and she made her payment on october 11, 2009, did she owe any interest on her last statement's balance?