The displacement (in meters) of an object moving in a straight line is given by s = 1 + 2t + ¼ t2, where is measured in seconds.
(a) Find the average velocity over each time period.
(i) [1, 3]
(ii) [1, 2]
(iii) [1, 15]
(iv) [1, 11]
(b) Find the instantaneous velocity when t = 1.