1 and 4 are tire.
2 and 3 are not.
Answer:
2.5
Explanation:2.5 +2.5 = 5.0
Answer:

Explanation:
From the question we are told that:
Frictional force 
Coefficient of kinetic friction 
Generally the equation for Normal for is mathematically given by

Therefore


Answer:
A fluids is any substance that flows. Air is made of stuff, air particles, that are loosely held together in a gas form. Although liquids are the most commonly recognized fluids, gasses are also fluids. Since air is a gas, it flows and takes the form of its container.
Explanation: