How many possible ways are there in arranging a red ball, a blue ball, and a green ball in a non-straight line using only two balls at a time?

I have a permutations & combinations geometry question.

Find the number of arrangements of the digits {0,1,2,3,4,5,6,7,8,9} such that the first digit is less than 7 AND the second digit is greater than or equal to 2.

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A farmer is raising chickens and cows. There are 42 total chickens and cows on his farm, in which there are a total of 140 legs. Assuming that all the chickens have 2 legs and all the cows have 4 legs, how many cows are on the farm?

Suppose Fred has 2 pairs of pants (blue and black) and 3 shirts (red, blue, and black).  Which of the following represents all of the outfits Fred could make with these options?

9 (b,c). The following data was collected from 1 bag of Hershey Kisses®. Each Kiss® was weighed in grams with the wrapper and recorded in the table below. Hershey claims that there are 368 grams of chocolate in one bag. The following data was collected from 1 bag of Hershey Kisses®. Each Kiss® was weighed in grams with the wrapper and recorded in the table below. Hershey claims that there are 368 grams of chocolate in one bag.     Hershey Kiss Weights in Grams 4.76 4.72 4.74 4.55 4.91 4.74 4.78 4.71 4.80 4.78 4.78 4.75 4.79 4.82 4.91 4.83 4.68 4.74 4.70 4.80 4.70 4.76 4.70 4.83 4.93 4.74 4.84 4.82 4.76 4.77 4.72 4.78 4.83 4.75 4.74 4.68 4.84 4.71 4.71 4.76 4.66 4.78 4.73 4.74 4.92 4.77 4.80 4.79 4.86 4.64 4.78 4.70 4.75 4.78 4.76 4.83 4.66 4.77 4.83 4.78 4.69 4.81 4.68 4.78 4.88 4.72 4.85 4.85 4.81 4.74 4.80 4.82 4.84 4.70 4.85 4.70 4.81 4.72 4.79 4.73 4.61   Standard Deviation & the Empirical Rule: Variation is a big factor in the analysis of most any…