If ¯¯¯a=^i+^j+^k,¯¯b=2^i+λ^j+^k,¯¯c=^i−^j+4^k and ¯¯¯a.(¯¯bׯ¯c)=10, then λ is equal to
If →r×→b=→c×→b and →r.→a=0 where →a=2^i+3^j−^k,→b=3^i−^j+^k and →c=^i+^j+3^k, then →r is equal to