Which is the equation of an ellipse with directrices at y = ±2 and foci at (0, 1) and (0, −1)? x squared over 4 plus y squared over 1 equals 1
x squared over 1 plus y squared over 2 equals 1
x squared over 1 minus y squared over 4 equals 1
x squared over 1 minus y squared over 2 equals 1

Apair of ordinary dice is rolled. what is the probability that each die will show a number higher than 4. 1. (1/36) 2. (1/12) 3. (1/6) 4. (1/4) 5. (1/3)

The administrator of a large assisted living facility wanted to know the average age of the residents living at the facility. he randomly selected 12 residents and determined their age, listed here: 80, 65, 75, 83, 68, 73, 88, 79, 94, 72, 79, 68 what's the average age of the sample of residents? a. 79 years old b. 68 years old c. 75 years old d. 77 years old

What is the expression in factored form? -x^2 + 3x + 28 a. (x-7)(x-4) b. -(x-7)(x+4) c. (x+4)(x+7) d. -(x-4)(x+7)