Answer:
Resistivity 
It depends upon cross sectional area and length of material
Explanation:
The resistance of any material is given by
, here
is the resistivity of material , l is length of material and A is cross sectional area
So resistivity 
So resistuivity of any material depends upon area of cross section and length of material
If cross sectional area will be more then resistivity will be more. And is length of the material will be more then resistivity will be less
Period, T, is 1/frequency
T = 1/340 = 2.941ms
Answer:
The volume of copper is 2.198 ml
Explanation:
Given;
mass of copper, m = 20 g
density of copper, ρ = 9.1 g/ml
Density is given by;
Density = mass / volume
Volume = mass / density
Volume = (20 g) / (9.1 g/ml)
Volume = 2.198 ml
Therefore, the volume of copper is 2.198 ml
It is called weathering. there are three different types of weathering, physical weathering, chemical weathering, and biological weathering. Your particular question is caused by chemical weathering.