I have a code,and i am going to do a for loop on two gamma distributions.

Given the list of shape parameter, and i name them "d" then i put in d[1] and d[2] in the random gamma function.

I have simplified what I wish to ask here. when i code d[1] in R, output will be the first vector,while when i code d[2] in R, output will be the second vector.
I have a bit lose then how will it iterate if i using for loop for d ?

```
*
List_1  <- list(c(4,16),c(16/9,4),c(1,16/9),c(.64,1),c(4/9,.64))
for ( d in List_1)  ##first parameter is for gamma.1, second is for gamma.2
{
 x<-rgamma(25,d[1],1)
 y<-rgamma(25,d[2],1)

 t<-t.test(x,y)$p.value
}*

```

I am sorry if i do ask a silly question. Thanks in advance.