Answer:
The total number of samples that give this outcome is 5.
Step-by-step explanation:
Since Y takes values in {0,1,2,3}, For us to have that 
implies that all of them are zero but one. The one that is non-zero necessarily is equal to 1. To calculate the number of samples that give this outcome is equivalent to counting the total number of ways in which we can pick the i-index such that 
. Note that in this case we can either choose Y1 to be 1, Y2 to be 1 and so on. So, the total number of samples that give this outcome is 5.
Answer: B, C, E
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The difference between consecutive terms (numbers that come after each other) in arithmetic sequences is the same. That means you add the same number every time to get the next number. To figure out which choices are arithmetic sequences, just see if the differences are the same.
Choice A) 1, -2, 3, -4, 5, ...
-2 - 1 = -3
3 - (-2) = 5
The difference is not constant, so it is not an arithmetic sequence.
Choice B) 12,345, 12,346, 12,347, 12,348, 12,349, ...
12,346 - 12,345 = 1
12,347 - 12,346 = 1
The difference is constant, so it is an arithmetic sequence.
Choice C) <span>154, 171, 188, 205, 222, ...
171 - 154 = 17
188 - 171 = 17
The difference is constant, so it is an arithmetic sequence.
Choice D) </span><span>1, 8, 16, 24, 32, ...
8 - 1 = 7
16 - 8 = 8
</span>The difference is not constant, so it is not an arithmetic sequence.
Choice E) <span>-3, -10, -17, -24, -31, ...
-10 - (-3) = -7
-17 - (-10) = -7
</span>The difference is constant, so it is an arithmetic sequence.
(-x-2) (x-4) are the factor of this equation
