Describe why it is difficult to implement a cache replacement policy that is optimal for all address sequences.

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?

Ihave been given the number of guns per 100, and the total firearm-related deaths per 100,000. i have to find the actual number of guns per country and actual number of gun-related deaths. if somebody could show me how to do 1 question, i can finish the rest, i am just confused. tia

What are the three uses of a screw?