which of the following is true if the given tree diagram with labeled probabilities represents independent events?

What is the number 321,000,000 in scientific notation? also what is the number? ?

The figure below shows rectangle abcd and the triangle eca on a coordinate plane.which of the following expressions represents the perimeter of triangle of triangle eca in units

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).