Two numbers that have a sum of zero are?

Any nymbers and such that

e.g.

1 and -1

35 and -35

698 and -698

1594589458934589 and -1594589458934589

1gm = 1000mg so 0.1gm = 1000mg

first, convert the weight to kg

160lb * 1kg/2.2lb = 72.7kg

next, the dose

72.7kg * 100mg/kg = 7270mg