silly mistakes [again]

ive just realized,,
during my fluid mechanics test,,
what i believed as specific weight was density.

SILLY..!!

ive checked, and my method is correct,
it just it.!
damn...!!

so, whats the difference between specific weight and density.
as u know, density is mass over volume,
while specific weight is density times gravity.
its not that i cant remember 9810 N/m^3 and 1000 kg/m^3
they gave it on BG unit..
62.4 lb/ft^3 i thought it was specific weight.
i shouldve multiplied it with 32.2 ft/s^2 [gravity]
whats the point of having BG units anyway,,
they've made SI units
why bother things with BG unit...???

damn,,,
again,,
i made some silly mistakes..