Answer: A) 98 kg
Explanation: Use the formula F=ma (force = mass x acceleration) and solve for mass. Plugging 225 N for F (which is the force) and 2.3 m/s^2 for a (which is the acceleration) you would get 225=m2.3. Divide both sides by 2.3 and you get 97.82, which is about 98 kg.