Ayana's chemistry class is exploring how the weight and volume of everyday objects are related. For her first experiment, Ayana gently drops a brick into a beaker filled with water. The volume increases by 2 liters, so now she knows the volume of the brick. Then, she uses its density to make a prediction about its weight in kilograms. If the density of brick is approximately 2 grams per milliliter, what should Ayana's prediction be?