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2) is the answer  8 and 6 respectively.
In body centered cubic packing structure model we have an atom at the center and eight atoms at the 8 corners of the cube. THese are the nearest neighbours for the atom at the center.  SO there are EIGHT. The distance between them is  diagonal of cube / 2 = √3/2 a.   a = size of the cube in the lattice
If you repeat the cubes around, you will see there are 6 cubes, one at each face of our cube. There is one at the center of the adjacent cube to our cube. That will be the nearest neighbour at the next level. The distance would be 'a' = size of cube in the lattice.

1 5 1
An element crystallise in a 'bcc' lattice. Nearest neighbours and next nearest neighbours of the element are respectively 8,6.