Eli is birdwatching and sees cardinals in a tree. After a gust of wind, 4 of the cardinals fly away. Circle the expression that shows the number of cardinals left in the tree.

To find out how many cardinals are left in the tree, you would take the total number of cardinals Eli initially saw and subtract 4 (the number that flew away). If we let \( C \) represent the initial number of cardinals, the expression would be \( C - 4 \). This expression captures the essence of how we calculate the remaining quantity after a loss—just simple subtraction at work! Birdwatching can be a delightful activity, and knowing how to keep track of animal populations can be vital for conservation efforts. Observing how many species are present and how many leave (like the cardinals) can inform how changes in the environment, such as weather events, impact local wildlife. So, every bird counts!