Answer;
Row to row
In a periodic table a set of properties repeats from row to row
Explanation;
In a periodic table, a set of properties repeats from row to row. This is called the periodic law. In the periodic table, the rows are called periods and the columns are called groups.
The modern periodic table is organized by increasing atomic number. The atomic mass unit is based on 1/12th the mass of a carbon-12 atom.
The atomic mass of an element is the weighted average of the masses of an element’s isotopes.
V=d*t
Since d=75km=75000m
t=1.5h=3600*1.5= 5400s
=>V=75000*5400
=405000000m/s=4.05*10^8m/s
The resistance of the cylindrical wire is 
.
Here 
is the resistance, 
is the length of the wire and 
is the area of cross section. Since the wire is cylindrical 
. Rearranging the above equation,
Here 
.
Substituting numerical values,
The length of the wire is 
Gravity is the attraction between two objects that have mass. The amount of gravity is directly proportional to the amount of mass of the objects and inversely proportional to the square of the distance between the objects. Gravity is a force that increases the velocity of falling objects - they accelerate.
