C Because Mesozoic Is An Era The First Fish Seen
Answer:
Physical properties are used to observe and describe matter. Physical properties can be observed or measured without changing the composition of matter. These are properties such as <em>mass, weight, volume, and density.</em>
Mass percentage of sodium chloride(NaCl) in ocean waters = 3.5 %
That means 3.5 g sodium chloride(NaCl) is present for every 100 g of ocean water.
The given mass of sodium chloride(NaCl) is 45.8 g
Calculating the mass of ocean waters that would contain 45.8 g sodium chloride(NaCl):

= 1309 g ocean water
Therefore, 45.8 g sodium chloride is present in 1309 g ocean water.
Answer:
Pat is most likely to have made the hydrofluoric acid.
Explanation:
How is hydrofluoric acid made?
It is manufactured by heating purified fluorspar (calcium fluoride) with concentrated sulfuric acid to produce the gas, which is then condensed by cooling or dissolving in water. ... The acid hydrolysis of fluorite-containing minerals generates an impure gas stream consisting of sulfur dioxide, water and HF.
that's all I got sorry
Answer:
Volume = 10ml
Density = 1/5 g/ml or 0.20g/ml
Explanation:
The rocks are 10ml since the initial volume went up by 10.
Since density = mass/volume, you divide 2 by 10.
D = 2/10
D = 1/5 g/ml or 0.20g/ml
(Unit is g/ml aka grams/millileter)