3 The length, \(x\) metres, of a Green Anaconda snake which is \(t\) years old is given approximately by the formula
$$x = 0.7 \sqrt { } ( 2 t - 1 ) ,$$
where \(1 \leqslant t \leqslant 10\). Using this formula, find
- \(\frac { \mathrm { d } x } { \mathrm {~d} t }\),
- the rate of growth of a Green Anaconda snake which is 5 years old.