\f3. Apply Newton's 2nd Law to write the equations for M1 and M2. You should get two equations with Tension in the string, weight for each mass and accelerations for each mass (a1 and a2), in variable form. 4. Pre-Lab Question 3 results in two equations with three unknowns. A third equation is required to solve the system. Formulate the third equation. (Hint: think about how the two accelerations relate to one another)