Compare the regression results for the three periods. Is there a notable change in the beta or the alpha? What about the statistical significance of the estimates? Please describe in detail and reference the data $($a$-$c$)$ a$.$

Before the crisis: February $1,2019-$ January $31,2020$

Intercept $=$ estimated Jensen's alpha $=0\mathrm{.}0012$

Mrkt premium $=$ estimated beta $=1\mathrm{.}2878$

b$.$

During the crisis: February $1,2020-$ March $31,2020$

Intercept $=$ estimated Jensen's alpha $=0\mathrm{.}0045$

Mrkt premium $=$ estimated beta $=1\mathrm{.}1571$

c$.$

During the recovery phase: April $1,2020-$ March $31,2021$

Intercept $=$ estimated Jensen's alpha $=-0\mathrm{.}0002$

Mrkt premium $=$ estimated beta $=1\mathrm{.}0758$