The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects where order of selection is important is called thea. counting rule for permutations.
b. counting rule for multiple-step experiments.
c. counting rule for combinations.
d. counting rule for independent events.

a. counting rule for permutations.

Step-by-step explanation:

-The special permutation rule states that anything permute itself is equivalent to itself factorial.

-The difference between a combination and a permutation is that order of the objects is not important for a combination.

-The permutation formula is:  (n)r = n! (n−r)!

the formula of a midpoint between a abd b:

add -60 to 120 which will result in : 2x+3y=180

then subtract 2x: 3y=-2x+180

lastly, divide by 2: y= -2/3x+60

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