Невозможно установить bcmwl-kernel-source

У меня проблемы с установкой беспроводных драйверов Broadcom на мой внешний жесткий диск с Ubuntu 20.04.2 LTS (ядро: 5.8.0-53-generic). Я загружаю с жесткого диска свой MacBook Air 2013 года выпуска. Вот информация о моей карте Broadcom ...

mk@mextern:~/Desktop$ lspci -nn -d 14e4:
02:00.0 Multimedia controller [0480]: Broadcom Inc. and subsidiaries 720p FaceTime HD Camera [14e4:1570]
03:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM4360 802.11ac Wireless Network Adapter [14e4:43a0] (rev 03)

Прочитав руководство здесь Установка драйверов беспроводной сети Broadcom , я решил, что мне следует установить пакет bcmwl-kernel-source (рекомендуемый пакет для карты 43a0). Однако, когда я пытаюсь установить это, я получаю следующий результат ...

mk@extern:~/Desktop$ sudo apt-get install bcmwl-kernel-source
[sudo] password for mk: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 bcmwl-kernel-source : Depends: dkms but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Я не уверен, что делать дальше. Я все еще новичок в среде Linux, поэтому любая помощь приветствуется.

Изменить: политика dkms

mk@mextern:~$ apt policy dkms
dkms:
  Installed: (none)
  Candidate: 2.8.1-5ubuntu2
  Version table:
     2.8.1-5ubuntu2 500
        500 http://us.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
        500 http://us.archive.ubuntu.com/ubuntu focal-updates/main i386 Packages
     2.8.1-5ubuntu1 500
        500 cdrom://Ubuntu 20.04.2.0 LTS _Focal Fossa_ - Release amd64 (20210209.1) focal/main amd64 Packages
        500 cdrom://Ubuntu 20.04.2.0 LTS _Focal Fossa_ - Release amd64 (20210209.1) focal/main i386 Packages

Попытка установить dkms

mk@mextern:~$ sudo apt-get install dkms
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 dkms : Depends: dctrl-tools but it is not installable
        Recommends: fakeroot but it is not going to be installed
E: Unable to correct problems, you have held broken packages.