This answer is not possible with only 3 attached atoms and 1 non-bonded pair of electrons. This results from an atom that has 2 non-bonded pairs of electrons and 3 atoms with sp³d hybridization (electron-pair geometry is trigonal bipyramidal). Draw the electron dot formula for ammonia and determine the number of atoms and non-bonded electron pairs that must be placed in hybrid orbitals. Then decide what arrangement the atoms are in...not the non-bonded pairs.