A train is moving at a speed of 60 m/s at 10.00 a.m. and at 80 m/s at 10:02 a.m. Assuming that the train moves along a straight track and the acceleration is constant, the value of acceleration is:

• A. \[300\,m/{{s}^{2}}\]   
• B. \[1/6\,m/{{s}^{2}}\]
• C. 6m2 
• D. \[6\,m/{{s}^{2}}\]
• E. None of these