▁engineering . ▁After ▁gradu ating ▁with ▁a ▁B A ▁in ▁ 1 9 7 9 , ▁he ▁served ▁various ▁roles ▁in ▁ref iner ies ▁before ▁becoming ▁executive ▁director ▁of ▁operations ▁at ▁N ET CO ▁in ▁March ▁ 2 0 0 5 . ▁In ▁addition ▁to ▁his ▁education ▁in ▁chem istry , ▁he ▁received ▁a ▁certificate ▁in ▁Str ategy ▁and ▁Organ ization ▁from ▁Stan ford ▁University ' s ▁Gr adu ate ▁School ▁of ▁Business ▁Studies . ▁He ▁left ▁his ▁N ET CO ▁role ▁in ▁December ▁ 2 0 0 6 ▁to ▁work ▁at ▁the ▁Niger ian ▁National ▁Pet role um ▁Corporation , ▁first ▁as ▁general ▁manager ▁and ▁ultimately ▁as ▁man aging ▁director ▁and ▁CE O . ▁He ▁assumed ▁the ▁role ▁several ▁months ▁after ▁a ▁national ▁fuel ▁crisis ▁in ▁Niger ia , ▁when ▁the ▁N N PC ▁was ▁widely ▁perce ived ▁as ▁a ▁cor rupt ▁organization , ▁and ▁o vers aw ▁changes ▁within ▁the ▁national ▁institution ▁until ▁he ▁was ▁removed ▁during ▁President ▁Jonathan ' s ▁regime ▁on ▁alleg ations ▁of ▁in sub ord ination . ▁Y ak ub u ' s ▁inter vention ▁led ▁to ▁the ▁gas ▁supply ▁to ▁the ▁Niger ian ▁market ▁growing ▁from ▁ 3 0 0 ▁million ▁cub ic ▁feet ▁per ▁day ▁( m cf pd ) ▁to ▁ 1 5 0 0 m cf pd , ▁of ▁which ▁ 7 0 % ▁was ▁dedicated ▁to ▁support ▁the ▁power ▁sector . ▁He ▁sust ained ▁stability ▁in ▁the ▁supply ▁and ▁distribution ▁of ▁pet role um ▁products ▁across ▁the ▁country , ▁with ▁Niger ia