How many pounds of coffee worth $6 a pound should be added to 20 pounds of coffee worth $3 a pound to get a mixture worth $4 a pound

What's the difference between: x≥0 and nonnegative integer. ?

Polygons efgh and e′f′g′h′ are shown on the coordinate grid: what set of transformations is performed on efgh to form e′f′g′h′? a. a translation 1 unit to the left followed by a 90-degree counterclockwise rotation about the origin b. a translation 1 unit to the right followed by a 90-degree counterclockwise rotation about the origin c. a 90-degree clockwise rotation about the origin followed by a translation 2 units to the right d. a 90-degree clockwise rotation about the origin followed by a translation 2 units to the left

What is the value of x? enter your answer in the box. x = two intersecting tangents that form an angle of x degrees and an angle of 134 degrees.