Boat Journey Problem Leading to a Quadratic Equation

The speed a boat in still water is \(55\) km/h and that of the current is \(x\) km/h.

1. Find an expression for the speed of the boat
   1. against the current,
   2. with the current.
2. Find an expression for the time required to travel \(120\) km
   1. against the current,
   2. with the current.
3. If the boat takes \(40\) minutes longer to travel against the current than it takes to travel with the current, write down an equation in \(x\) and show that it can be expressed as \({{x}^{2}}+360x-3025=0\).
4. Solve the equation \({{x}^{2}}+360x-3025=0\), giving both answers correct to two decimal places.
   
5. Find the time taken to travel \(80\) km with the current.