Misc: What is foil brand name Alcan an abbreviation of?

Questions

who heard it through the grapevine in 1968?

who did yusufa k. lule replace as his african country's leader in 1979?

what magazine started inviting readers to crease the back cover on folds a and b?

what looked like alka-seltzer but tasted like soda pop?

what sleepy crooner's first million-seller was a tune called temptation?