the expectation students often have when doing the coin flip experiment is that thye will flip exactly 5 heads and 5 tails because there is 50% chance of flipping each. Is this a realistic expectation

No

Explanation:

A coin which has a head and a tail has 1/2 probability of each which is a 50% chance of getting either a head or a tail. This means that given two sides of a coin, probability looks at the number of favorable outcomes and total number of outcomes, a formula that reflects a pattern seen in past experiences. Probability isn't absolute but relative. When we say there is a 50% chance of getting a head in a coin flip, it is relative to past experiences but doesn't assure of particular future occurrences regarding the coin flip.

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right