díganme del 1 al 4 cuál fue primero la era musulmana la caída del imperio romano occidente las cruzadas o la caída del imperio romano bizancio? por favor​

Which number shows the location of the united kingdom of great britain? 7 5 2 4

Can someone me choose a broad topic and area of focus i am really doing this as a tally to see which one most people pick ok water pollution global warming endangered species atmosphere for the !

Asap! ! ! ! true or false the gobi desert, the largest desert in asia. covers parts of northern china and southern russia