Write the name of this property 42+0 = 42

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?

There are a total of 75 students in the robotics club and science club. the science club has 9 more students than the robotics club. how many students are in the science club?

Aconstruction worker needs to put a rectangular window in the side of a building he knows from measuring that the top and bottom of the window have a width of 8bfeet and the sides have a length of 15 feet he also measured one diagonal to be 17 feet what is the length of the other diagonal