two parabolas have the same focus . their directrices are x and y axes. the absolute value of the slope of the common chord is

Classify each action depending on whether it will meet or fail to meet the goals of the organization. a group of students form a healthy earth club at their school. their goal is to limit their school’s impact on human-led climate change. they brainstormed a list of actions they can take to meet this goal.

31. all the following are effective ways of preparing for an interview except practicing in front on a mirror writing down answers to possible questions holding a mock interview with a friend memorizing interview questions and answers

Raul has one solution that is 20% acid by volume and one solution that is 50% acid by volume. he plans to mix together some of each solution to create 30 milliliters of a solution that is 40% acid by volume. how many milliliters of the 20% acid solution should raul use to create the 40% acid solution? can someone explain this to me? i know that the answer is 10 milliliters, but i don't know how to get it.