1.4
import numpy as np
import matplotlib.pyplot as plt
import scipy.stats as stats

x = np.arange(0,10,0.05)
y = stats.chi2.pdf(x, 2)
plt.plot(x, y, 'gray')

x = np.arange(0, 10, 0.05)
y = stats.chi2.pdf(x, 3)
plt.plot(x, y, 'orange')

x = np.arange(0, 10, 0.05)
y = stats.chi2.pdf(x, 5)
plt.plot(x, y, 'green')

x = np.arange(0, 10, 0.05)
y = stats.chi2.pdf(x, 10)
plt.plot(x, y, 'red')


plt.show()

print(1-stats.chi2(20).cdf(10.9))
print(stats.chi2(20).cdf(28.9))
print(stats.chi2(25).cdf(31.4)-stats.chi2(25).cdf(8.26))