need help with Type Casting

[Teny]

So i got this homework where i got stuck at. My class is using Java.
I dont quite understand what Type Casting do, or how to do it. Heres the problem

Assume the following declarations

int integer ;
double preciseReal ;
float sloppyReal ;
long bigInteger ;

Rewrite those of the following statements which would generate a compile-time error using an appropriate cast that makes the error go away. Do not provide a cast for any statement which the compiler automatically promotes.

a) integer = preciseReal ;
b) bigInterger = sloppyReal ;
c) preciseReal = integer ;
d) sloppyReal = bigInteger ;
e) integer = sloppyReal ;
f) bigInteger = preciseReal ;
g) sloppyReal = integer ;
h) preciseReal = bigInteger ;
i) integer = bigInteger ;
J) sloppyReal = preciseReal ;
k) preciseReal = sloppyReal ;
l) bigInteger = integer ;

Now, Im not asking you guys to do my homework for me. But maybe make it a bit easier for me to understand. I read the section in the book, and a couple things I googled, and I just got lost. Any help would be appreciated, and if you can, do an example from above if possible.

Thanks

EDIT - Nevermind, I got it.