Which desert is located in the Horn of Africa?

What is the name of the mountain range that includes Mount Elbrus? In which continent is the Atacama Desert located? In which country is the Thar Desert located? What is the name of the desert that covers parts of Argentina and Chile? What is the name of the largest desert in South America? In which continent is the Namib Desert located? What is the name of the desert that covers parts of China and Mongolia? What is the name of the desert that covers parts of Saudi Arabia and Yemen?