Solving a problem in physics section 26 point 4 mechan

4. Body weight m = 4 kg under the action of some force moves linearly in accordance with equation s = Bt + Ct2 + Dt3, where B = 0.5 m / s, C = 3 m / s2, D = 2 m / s3. Define A work force during the first two and a half seconds.