A bag contains 2 red marbles and 3 black marbles. If Abby picks a marble without looking, returns it to the bag, and then draws a second marble, what is the probability that both marbles are red? Give the answer as a fraction in simplest form

Is the orthocenter of a triangle on the inside ?

What is the perimeter of a rectangular building that is 80 feet wide and 140 feet deep?

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)