Its number four.Hope that helps feel free to ask me questions:)
Brainliest??
There are multiple factors that contribute to the cost of a mineral.
First of all is the demand or application, which will be related to its
physical properties. For example, nontarnishing metals like gold are
held in high value for their appearance. Second is the supply of the
mineral, those that only have a small quantity in the earth's crust are
likely to be more expensive. Third is the cost of extraction and
manufacturing. Some minerals may be abundantly found, but may be
distributed over a wide area, meaning that it is still expensive to mine
and transport.
Explanation:
a) 3Pb(NO3)2 + Al2(SO4)3 ---> 3PbSO4 + 2Al(NO3)3
Double displacement
b) 2Cl2 + 3O2 ---> 2Cl2O3
Synthesis
c) 2Fe2O3 + 3C ---> 4Fe + 3CO2
single displacement
The mass number goes on top, and the atomic number goes on bottom.
Therefore, the answer is C:
40
K
19
Answer:
A) Energy is needed to start photosynthesis and is a product of cellular respiration.
Explanation:
