OPEN NATIONAL INVITATION TO TENDER N° 001/ONIT/MINESEC/NWR/DMD/DMDTB/2021OF 04/02/2021 FOR THE CONSTRUCTION OF A BLOCK OF TWO CLASSROOMS AT GOVERNMENT SECONDARY SCHOOL (G.S.S) NYANJI IN NKAMBE, DONGA MANTUNG DIVISION, NORTH WEST REGION