Often a radical change in the form of the solution of a differential equation corresponds to a very small change in either the initial condition or the equation itself. Find an explicit solution of the given initial-value problem. Use a graphing utility to plot the graph of each solution. Compare each solution curve in a neighborhood of (0, 1).

1. dy/dx = (y -1)², y(0) = 1

2. dy/dx = (y - 1)², y(0) = 1.01

3. dy/dx = (y - 1)² + 0.01, y(0) = 1

4. dy/dx = (y - 1)² – 0.01, y(0) = 1