Given the statements below, choose the one that is true about one-celled living things. Under normal conditions, yeast produces spores.
The adult stage for one-celled organisms is usually extremely long.
Algae can only be unicellular.
Because of its size, algae does not make much oxygen for the earth.

The adult stage for one-celled organisms is usually extremely long.

Explanation:

The first one is false, I'm no expert, but I'm pretty sure that there is some yeast that don't produce spores, even in normal conditions.

The third is false, Algae can be unicellular and multicellular.

The fourth is false, All the Algae in the world is close to half  of the ogygen in the world.

So that leaves the second, The adult stage is usually long for one-celled organisms.

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.