Soil with high amounts of what is acidic

Four objects are being tested to see how they are affected by fluid friction. object w has a surface area of 4.5 cm2, object x has a surface area of 2.5 cm2, object y has a surface area of 6.2 cm2, and object z has a surface area of 3 cm2. which object would experience the most fluid friction?

What is created when solids,liquids,an gases mix with one another

Which articulations allow for greatest range of motion?