Physical Barriers to Communication Technology
Handling physical barriers when using mobile phones and radios
5 Pillars of Total Defence
5 Pillars of Total Defence.
(Ed. Note: "Defense" is preferred in American English, and "defence" is preferred in all other main varieties of English)
Total Defence
Match the correct pillar to the description.
Social Media Users and Activities (Idioms 2)
Facebook and social media users
