Which team holds a "Racing Presidents" race during home games?

What happens on April 15 each year in MLB? What is the home run celebration feature at Citi Field that rises from center field? Which team's mascot is the Phillie Phanatic? Which team's mascot is Mr. Met? Which team holds a "Sausage Race" during home games? Which team's mascot Bernie slides down a slide after home runs? Which team's mascot is Wally the Green Monster? Which team's fans made the "Rally Monkey" famous in 2002?