As we know that,
e=PSPM
Where, PS is distance from fixed point and PM is distance from fixed line.
1. For circle PM is equal to infinity. So, the ratio will be zero which concludes e = 0.
2. For ellipse PS is less than PM. So, the ratio will be less than 1. which concludes e < 1.
3. For parabola PS is equal to PM. So, the ratio will be equal to 1. which concludes e = 1.
4. For hyperbola PS is greater than PM. So, the ratio will be greater than 1. which concludes e > 1.