LVM - Physical volume size

Hello

I have two questions :

1)
I have a Linux machine with 4 x 2.2TB in RAID 5.
So it gives one single virtual disk of 6.6 TB

The first strange thing is that lsblk gives :

sda 8:0 0 80G 0 disk
sda1 8:1 0 1G 0 part /boot
sda2 8:2 0 79G 0 part
rhel-root 253:0 0 47.7G 0 lvm /
rhel-swap 253:1 0 8G 0 lvm [SWAP]
rhel-home 253:5 0 23.3G 0 lvm /home
sdb 8:16 0 80G 0 disk
vg_ids-lv_IDS 253:2 0 38G 0 lvm /IDS
vg_ids-lv_IDS_prev 253:3 0 38G 0 lvm /IDS_Prev
vg_ids-lv_prod 253:4 0 4G 0 lvm /prod
sdc 8:32 0 2T 0 disk

So we have sda, sdb, sdc
Apparently I miss something, but how from one physical volume I get 3 devices.

2)
The second prob is that I get from lsblkor pvs
sda 80G
sdb 80G
sdc 2T

[root@ids-dr ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 rhel lvm2 a-- <79.00g 0
/dev/sdb vg_ids lvm2 a-- <80.00g 0
/dev/sdc vg_dbpaces lvm2 a-- <2.00t <14.00g

And when creating a physical volume, the size is not specified and it has to take the whole volume, so where are the missing 4.6 TB.

Thanks