alph0 = 35*π/180;
gamm =  .03;
v0 = 155;
v0x = v0*Cos[alph0];
v0z=v0*Sin[alph0];
g = 9.8;
tR = 2*v0z/g;
%
Plot[{v0z*tt -  .5*g*tt^2, -g*
                  tt/gamm + (gamm*v0z + g)*(1 - Exp[-gamm*tt])/
                    gamm^2}, {tt, 0, tR}, PlotLabel -> "Projectile", 
            AspectRatio -> 1, AxesLabel -> {"t", "z"}, 
            PlotRange -> All, 
            PlotStyle -> {Dashing[{ .001,  .01}], Dashing[{1, 0}]}];