The spread of a disease in a community is modelled by the following differential equation:

dy/dx = 0.2y - 0.02x where y is the number of infected individuals in thousands, and x the time in days.

1) Show the equation that for the family of 'curves' in the plane for which dy/dx is a constant, is the form y=mx+c.

2) Solve the equation using the linear 1st order method, given that initially there are on thousand infected individuals.