How many kills total do I need to complete these challenges.
All Equipment besides Black Hat and Grenade
Return to Sender
VTOL Warship Kills
K9 Unit Kills
Baked to Perfection
Eyes in the Sky
Down and Out
I haven't even started on them.*Edit*
And I mean in total not by tier.
For killstreaks its 50 kills.
Iron sights 500 kills and dual band and any other optic.
Eyes in the sky: 100 kills while vsat is active
Down and out 100 kills while emp is active
Emp support : 2500 assist points from emp
Orb support: 2500 assist points from vsat
LMG kills: 1000
Overkill: 500 kills in the same life using a primary then switching to a secondary
Duel wield :500 kills
Scorestreak kills need 50, VSAT and EMP need 100 kills/ 1000 assist score, LMG kills need 1000.
Not sure on the rest, but the CoD wiki should have definitive values.