Answer: The question is not complete as options are not complete , the remain part are;
A. 3.7 years, photosynthetic bacteria.
B. 3.7 years cyanobacteria.
The correct option is
3.7 billion years old, cyanobacteria and stromatolite.
Explanation:
This is because cyanobacteria is the oldest fossil to exist and they have been in existence for about 3. 7 billion years. These cyanobacteria photosynthesized because they have thread like chlorophyll filament, they produce food through the process of photosynthesis which is needed for their survival and they release oxygen as bye product.
Answer:
1,5,2,3,4
Explanation:
I'm not sure about this, so take this answer with a grain of salt. I think you would fill in the blanks like this: 1,5,2,3,4.
Answer:
In which class of elements is there a greater range of properties, the metals or the nonmetals? Give an example to support your answer. Non-metals have greater range of properties given that they exist as solids, liquids and gases. And also that they can polymerize, crystallize and form organic compounds.
Answer:
C.22 grams because mass cannot be created or destroyed
Explanation:
Reaction equation:
2H₂ + O₂ → 2 H₂O
Mass of oxygen = 18g
Mass of hydrogen = 4g
The mass of water produced is 22g according to law of conservation of mass.
The law states that " in a chemical reaction, mass is always conserved"
The sum of the mass of product and reactants must always be the same.
