1) which is not a way to know if a chemical change has occurred? a. heat is absorbed or released b. phase change occurs c. new color d. new substance is made 2) is co2 a reactant or product? 3) is o2 a reactant or product? (2 and 3 are combined i just made them two separate questions)

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?