<PRE><B>Question 371877</B>
Mass is the product of density and volume.
Convert mm to m to be consistent in units.
The volume of a sphere is,
{{{V=(4/3)*pi*(D/2)^3=(pi/6)(25/1000)^3}}}
{{{V=6.54x10^(-5)}}}{{{m^3}}}
Then 
{{{m=rho*V=250*6.54x10^(-5)}}}
{{{m=0.01636}}}kg
{{{highlight(m=16.4)}}}grams
Then use a conversion of 454 grams=16 ounces
{{{m=16.4(16/454)}}}
{{{m=0.58}}}ounces</PRE>