John has 6 green marbles and 4 purple marbles. he chooses a marble at random, writes down its color, and then puts the marble back. he performs this process 5 times. what is the probability that he chooses exactly two green marbles?

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.

What is 0.000008 meters in scientific notation