shower are electrons (both signs) and it is their state i. e. distributions over several variables at various atmospheric levels that we are concerned about in this work.\
We find the number of electrons $\Delta N(\theta, \varphi,r/r_M,E;s)$ in variable bins $\Delta\theta \Delta\varphi\Delta (log\,r/r_M)\Delta log\,E$ at various ages $s$. Our study is restricted to variable regions where there are most electrons in the shower, i.e. to $0.7< s <1.3$, $20\,\textrm{MeV}< E <200\, \textrm{MeV}$ and $r/r_M<1.5$. The lower energy limit was chosen mainly by our final interest to describe the shower Cherenkov radiation with the threshold $E=21$ MeV at sea level and increasing with height. For $E<20$ MeV the accurate electron angular distributions are not necessary for the purpose of reconstructing shower properties from the optical data because the fluorescence light is emitted isotropically. However, our parametrizations fit well down to $\sim 15$ MeV.\
Single showers with $E_0 =10^{17}$ eV and $10^{16}$ eV were fully simulated i.e. without using the thinning procedure [@hillas2], whereas at $10^{18}$ and $10^{19}$ eV the thinning (a procedure constraining the number of followed particles by assigning to some of them a weight) was, of course, used.\

![Distributions $f_{\varphi}(\varphi;r/r_M,E,s)$ of electron azimuth angle $\varphi$, integrated over polar angles 