Application in the derivative ..?

I hope that someone help me in solving these application. (plz, I want to solution step by step)..

Q1:

A Cassna plane takes off from an airport at sea level and it's altitude (in feet) at time t (in minutes) is

given by h= 2000 ln (t+1) .

find the rate of climb at time t = 3min .

Q2:

If the variable sound power W is given by W = T^2 + t + 1 , Find the rate of change of the sound

pressure P , at time t= 3 s .

Q3:

A computer is programmed to inscribe a series of rectangle in the first quadrant under the curve of y=e^-x

What is the greatest area of the largest rectangle that can be inscribed ? .

Q4:

A point moves along the x axis so that it's position x at time t is specificed by the function x(t)= t^3-8t+8 .

determine the following :

a- the acceleration at times when the velocity is zero .

b- the average velocity over the time interval (0,6) .

I'm sorry for all this quastion ..