Good Riddles

Question: A detective who was mere days away from cracking an international oil smuggling ring has suddenly gone missing.While inspecting his last-known location,officers find a note:710 57735 34 5508 51 7718.Currently there are 3 suspects:Bill John,and Todd. Can you break this answer and tell me the reason.

Question: how do cows count?

Question: I attach to your hip and I sing all day.
All I want to do is play.

Question: It breaks away from its pack. It creates holes in its victims. It can travel for miles and then disappear. It is part of a dying breed. What is it?

Question: It's got twists and turns, but has no curves.
Twist it to fix it, turn it to ruin it.

What is it?