Can you please help me with 2,3,4 and 5. Will mark brainliest.

X^2/100+y^2/25=1 the length of the major axis is: a)5 b)10 c)20

Exclude leap years from the following calculations. (a) compute the probability that a randomly selected person does not have a birthday on october 4. (type an integer or a decimal rounded to three decimal places as needed.) (b) compute the probability that a randomly selected person does not have a birthday on the 1st day of a month. (type an integer or a decimal rounded to three decimal places as needed.) (c) compute the probability that a randomly selected person does not have a birthday on the 30th day of a month. (type an integer or a decimal rounded to three decimal places as needed.) (d) compute the probability that a randomly selected person was not born in january. (type an integer or a decimal rounded to three decimal places as needed.)

What does the pair of equations y = 1, z = 8 represent? in other words, describe the set of points (x, y, z) such that y = 1 and z = 8?