Answer:
The ratio of electric force to the gravitational force is 
Explanation:
It is given that,
Distance between electron and proton, 
Electric force is given by :

Gravitational force is given by :

Where
is mass of electron, 
is mass of proton, 
is charge on electron, 
is charge on proton, 



So, the ratio of electric force to the gravitational force is
. Hence, this is the required solution.
Answer: height = 3.98m
Explanation: by placing the watermelon at a height above the ground, it has a potential energy of the formulae
p = mgh
p = potential energy = 4.61kJ = 4610J
m = mass of watermelon = 118 kg
g = acceleration due gravity = 9.8 m/s²
4610 = 118 * 9.8 * h
h = 4610/ 118 * 9.8
h = 4610/ 1156.4
h = 3.98m
The international system of units is the designated system of units used by scientist in every part of the world to keep data in the same form and measurements, this is to avoid confusion and the need to convert data when being shared. typically described in meters or kilometer over a time form usually seconds or hours.