Optical sensor basics

I am very new to electronics, and have been asked to desingg a extremely simple system that only contains a relfective optical sensor( link datasheet below)

My Vcc is 5 volt

i know i need two resisitors

One resistor load connected to the photodiode calaculated with Rl= (vcc-vf)/If

and another connected to the emitter of my transistor(With Ie= 100uA and Vec = 5 v) I am not sure which formula to use to calculate this resistor?

http://www.vishay.com/docs/83751/cny70.pdf

I am not sure if finding the load line is neccesary for this? and how if so? I'd really apreciate some help since i'm in quite of a pinch on this one

Looking at the data sheets, distance and reflectance play a part in determining the design, if you look at the graphs(figs. 6 and 9), the collector current is specified for an LED forward current with a fixed reflectance and distance. My guess is you are going to have to play around with the circuit to get the results you need.
You don't say if the device is acting as a switch, or you need an analogue response,
cheers,
Richard