In the figure above, lines x and y are parallel and intersected by line p. What is
the value of a? ( please answer quickly )

Aboard game uses a fair six-sided die and a spinner with five equal-sized sections colored dark blue, green, light blue, red, and yellow. players roll the die and then spin the spinner. match each probability statement to its correct value.

How to do this , and can some one explain

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).