serendipityii174 serendipityii174 29-01-2024 Physics contestada A force of 1200 N is used to stretch a spring with 0.8 kg attached to it. If the spring stretches 4 meters, what is the spring constant (k)? A: 4,800 N/m B. 1500 n/ m C. 960 N/m D. 300 n/m