help #2

Hi...im lack of experience doing scientific calculator that is exactly like real scientific calculator with some design....

somehow in the internet,the scientific calculator is for the simplest one..

here i dont understand how to
1) write a code for memory in and memory recall
2) scientific features and functions (sin(),log,fx,10^x,e^x,sqr(),
hex,dec,oct,bin,qword,dword,byte (by using option button) ,backspace,mod,or,run 1/x and other features
3) code for shift key & replay key features
it says must usd one dimensional array or control array feature whenever it is necessary...

i need a guide or explanation for each code,so that i can understand it very well...:)..thanks once again