B. One
because an independent variable is something you change. So in a scientific experiment you only change one thing. If you happen to change more than one thing then the test becomes unfair therefore you should repeat and make sure that only one thing is changed this time.
The superscript of element Cl⁻ indicates it is a negative ion.
Answer:
Cell theory
Explanation:
Cell theory is a universal theory proposed by three scientists namely: Theodor Schwann, Mathias Schleiden and Rudolf Virchow in the 1830's. The cell theory compose of three components:
- All living things are made up of one or more cells.
- Cells are the basic and fundamental unit of life
- All cells emanate from pre-existing cells.
Based on this question, these three components are what makes up the CELL THEORY.
The fir tree can be found in the coniferous forest biome, and the cactus can be found in the desert biome.
Option C.
<h3><u>Explanation:</u></h3>
Both the cactus and fir trees are having modified tree leaves due to the same purpose - saving water.
The fir trees are found in the coniferous forests which are mainly seen in mountains or in the temperate region. Both the regions face very cold climates and frequent snowfalls in every years. This is why there's a lack of water in the surroundings. This is why they need to save water and minimize transpiration.
Whereas the cacti are found in desert or semi arid regions where water is itself very scarce and temperature is either very high or very low. So they have their leaves converted into spines which help to reduce transpiration.
I think format? or formula?