What is the formula to find out the diameter of pie . i am trying to find out the area of circles

If you measured the width of a window in inches and then in feet with measurement would you have the greater number of units

What multiplys to be 1 but adds up to be 4

The monthly texting plan of all star cell is $11 per month and $0.25 per text. the monthly texting plan of top line cell is $14 per month and $0.15 per text. a student wants to set up a system of equations to find the number of texts for which the total monthly cost of the two companies is the same. he uses the variables x and y. he lets y represent the total monthly cost. what will x represent? x = number of texts x = cost of the total number of texts x = total monthly cost x = cost of each text