Generally, you measure dry weight on a scale.
biomass
This cannot be sensibly answered. Milliliters (mL) is a measure of volume, dry ounces are a measure of weight or mass.
A hamper is a measure of volume used for dry goods like fruit or grain, typically equivalent to 2 bushels. It is not a measure of weight.
A kilogram is a measure of mass, not of weight. They are not the same thing!
dry measure
You can measure weight or mass in grams. Grams are commonly used to measure small quantities of ingredients in recipes or to weigh objects.
The total dry mass of an organism equals biomass. How biomass is measured depends on why it is being measured. It can be measured as the natural mass or as it is. It can also be measured in terms of dry, organic mass. And sometimes just tissues count or just bones.
You don't A count per second is a measure of how many decays occur within a second. A sievert is a measure of the dose equivalent. This requires knowledge of the isotope, the organism or part of the organism which is receiving the dose, the weight of the organism and the weighting factors which accompany them.
A peck is a measure of dry volume - not of weight. 8 dry quarts (16 dry pints) - note not for liquids. Thus the weight would depend on what was being measured: feathers or lead sinkers.
To work out a pyramid of biomass, the dry masses of an organism is used because two of the same organisms could live in two different environments where one environment could be suffering from a drought whereas the other could live in a rain forest so to keep it fair they dry it out.
You can't, millilitres is a measure of VOLUME Ounces is a measure of WEIGHT The two can not be equated without knowing the density of the matter being measured.
You can measure a dry tampon, then measure one that's saturated, and calculate the difference in weight to calculate the capacity. Using water is sufficient.