In each of the following problems, a number is given. If possible, determine whether the given number is rational or irrational. Justify your answers.

Describe all the numbers that when rounded to the nearest thousand are 645,000

Astudent draws two parabolas on graph paper. both parabolas cross the x-axis at (-4, 0) and (6,0). the y-intercept of thefirst parabola is (0, –12). the y-intercept of the second parabola is (0-24). what is the positive difference between the avalues for the two functions that describe the parabolas? write your answer as a decimal rounded to the nearest tenth.

If sin(x) = 0 and cos(x) = 1, what is tan(x)?