1) The derivative of af+ bg, where a and b are numbers and f and g are functions, is af'+ bg'. And the derivative of [itex]x^n[/itex], with respect to x, is [itex]nx^{n-}[/itex].

2) Same as (1). I presume you want to differentiate p with respect to e. And so I am assuming that "e" is NOT the base of the natural logarithm, a constant.

3) The derivative of ln(u), with respect to u, is 1/u. You also need the "chain rule": if f is a function of u and u is a function of t, df/dx= (df/du)(du/dt). Here, u= t/10.

Surely these "rules" are in our textbook?