Pikachu gets the question wrong, and is shoved down the mountain. Before he finally perishes (FINALLY), he is caught by a young boy named Justin (NOOO WHYYY). Justin is only five years old. Pikachu sends him tumbling down the mountain, and when they are both about to die, they land in a rectangular prism-shaped pool, that measures 30 miles long, 60 miles deep, and 1 mile wide. Given that the volume of Justin is 135 miles cubed + n, and the volume of Pikachu is 45 miles cubed + the additive inverse of n, how much higher will the water level rise, in miles?