If vectors AB→=−3i^+4k^ and AC→=5i^−2j^+4k^ are the sides of a ∆ABC, then the length of the median through A is
14
18
29
5
AB→+AC→=2AD→∴ AD→=12{(−3i^+4k^)+(5i^−2j^+4k^)}=i^−j^+4k^
Length of AD=1+1+16=18