A model for the height, hhh metres, of a fast-growing bamboo pole ttt weeks after it is planted is given by h=1.2+4ln(2t+1)h = 1.2 + 4 \ln(2t + 1)h=1.2+4ln(2t+1), for t≥0t \ge 0t≥0. Determine the exact rate of growth of the bamboo pole, in metres per week, at the instant when the height of the pole is 9.29.29.2 metres.