Can you me with 7 and 8 find the slope of the line

Which radical expression is a rational number? a. √ 360 b. √ 644 c. √ 225 d. √ 122

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 is solution for the following system of equations, 2x+8y=4 and x=-3y+5 1) x=14 y=-3 2) x=2 y=-3 3) x=-3 y=-3 4)x=12 y=5