Which two factors contributed to the spread of islam in africa? (btw its two factors not just 1) a) islam was already practiced by people in africa. b) many africans no longer believed in their own religions. c) the islamic empire extended into north africa. d) the gold-salt trade brought islamic arabs into western and southern africa.

C) The Islamic Empire extended into North Africa.

D) The gold-salt trade brought Islamic Arabs into western and southern Africa.

d) the constitution rights of native americans and their right to self-government on reservations

the steam engine.

the locomotive.

the telephone.

the telegraph.

the internal combustion engine.

the rifle.

ironclad ships.

electricity/light bulb.