Electrostatic force problems, help

[StudentPhys]

Electrostatic force problems, help urgent!

Homework Statement

Question: An isolated hollow metal sphere of radius 40 cm carries a charge of -10*10^-6.
What is the magnitude of the electric field E (a) in the empty space inside the sphere and (b) 60 cm from the center of the sphere ( no picture provided )

Homework Equations

Electrostatic force= K * q1*q2/ d^2

The Attempt at a Solution

I´ve tried to use Coloumb´s law to get to the correct answer , what I am having trouble to realize is 1. is there even an electric field within a hollow sphere,? and 2. do you count the distance in problem B from the surface of the sphere or from the center? I tried the center , and i got the wrong answer, don´t know if that is the problem. HELP URGENT , test coming up! :O :(

 

[tiny-tim]

Welcome to PF!

Hi StudentPhys! Welcome to PF!

Show us your full calculations, and then we'll see what went wrong, and we'll know how to help!

 

[StudentPhys]

Hi StudentPhys! Welcome to PF!

Show us your full calculations, and then we'll see what went wrong, and we'll know how to help!

My calculations are as follows:
I went on the assumption, having read it somewhere, that the electric field within a metallic sphere have 0 magnitude. and wrote E=0
and secondly 2) E= (9*10^9)(-10*10^-6)/ (0,6^2)= 32364 N/C

Though the key says these answers are incorrect , is this so or is the key wrong?