Aws_instance with specific AZ

Terraform Providers AWS
2

Looks like this worked:

 db_subnets                      = data.terraform_remote_state.network.outputs.database_subnets

resource "aws_instance" "slave01" {
  subnet_id                   = element(var.db_subnets, 0)

resource "aws_instance" "slave02" {
  subnet_id                   = element(var.db_subnets, 1)

resource "aws_instance" "slave03" {
  subnet_id                   = element(var.db_subnets, 2)

But is there a better way to achieve this?