(a) To find the value of k, integrate the acceleration to find the velocity:
\(v = \int (2t - \frac{3}{5}t^2) \, dt = t^2 - \frac{1}{5}t^3 + C\)
Since the cyclist starts from rest, \(v = 0\) when \(t = 0\), so \(C = 0\).
Set \(v = 0\) to find \(k\):
\(t^2 - \frac{1}{5}t^3 = 0\)
\(t^2(1 - \frac{1}{5}t) = 0\)
\(t = 0\) or \(t = 5\)
Since \(t = 0\) is the starting point, \(k = 10\).
(b) The maximum speed occurs when acceleration \(a = 0\):
\(2t - \frac{3}{5}t^2 = 0\)
\(t(2 - \frac{3}{5}t) = 0\)
\(t = 0\) or \(t = \frac{10}{3}\)
Substitute \(t = \frac{10}{3}\) into the velocity equation:
\(v = (\frac{10}{3})^2 - \frac{1}{5}(\frac{10}{3})^3\)
\(v = \frac{100}{9} - \frac{1000}{135}\)
\(v = \frac{800}{135} = \frac{8\sqrt{30}}{9} \approx 4.87 \text{ m/s}\)
(c) Integrate the velocity to find displacement:
\(s = \int (t^2 - \frac{1}{5}t^3) \, dt = \frac{t^3}{3} - \frac{t^4}{20} + C\)
Substitute \(t = \frac{10}{3}\) and \(t = 10\) to find the distance:
\(s(\frac{10}{3}) = \frac{(\frac{10}{3})^3}{3} - \frac{(\frac{10}{3})^4}{20}\)
\(s(10) = \frac{10^3}{3} - \frac{10^4}{20}\)
Distance = \(s(10) - s(\frac{10}{3}) \approx 20.7 \text{ m}\)