ask user to choose
 

in column A i have dates
in column B i have BP stock price
in column C i have brent crude values

in cell j2 , i calculate = slope(b, c )...

now if i have data in column D ie the beta exposure , i dont neeed the
formula from cell j2...

i want to be able to have a product of values of crude dat with the
beta exposure ( i mean multiply column c with D )...for each of those
dates....

how do i ask the user to choose whether to choose option A( slope ) or
B ( data from column D method )... using a macro ....

i want the user to be asked whether he has beta values or not .
if he says no , then it shud calculate the slope ( b, c )

if yes , then he shud multiply as told above ..