Questions without answers in BJT

Figure shows the output characteristics of two different Bipolar JunctionTransistors (BJT), BJT $1$ with magnitude of Early voltage $\left|V_{A 1}\right|$, and BJT $2$ wi...

A small signal source, $V_{i}(t)=A \cos \left(10^{5} t\right)+B \sin \left(10^{7} t\right)$ is applied to a BJT circuit as shown in the Figure.Assume zero source resistan...