Markus has a box containing 10 red cards, 10 yellow cards, 10 blue cards and 10 green cards. He randomly selects one card, records the color, and then replaces the card in the box. If he does this 300 times, about how many times should Markus expect to draw a yellow card?

Antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

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