Answer: A) 
Explanation:
The equation for the moment of inertia 
of a sphere is:
(1)
Where:
is the moment of inertia of the planet (assumed with the shape of a sphere)
is the mass of the planet
is the radius of the planet
Isolating from (1):
(2)
Solving:
(3)
Finally:
Therefore, the correct option is A.
The eaths radius is the correct answer, if you need proof look at nasa's website
Answer:
Biasing - Biasing means being unfair to someone or something, and liking the other one or helping them.
Doping - Doping is where a person use drug to get better at sporting and get stronger muscles, such as getting stronger, getting faster and so on. It is mostly used by athletics.
Answer:
= 391.67 Hz
Explanation:
The sound of lowest frequency which is produced by a vibrating sting is called its fundamental frequency ().
The For a vibrating string, the fundamental frequency () can be determined by:
= 
Where v is the speed of waves of the string, and L is the length of the string.
L = 42.0 cm = 0.42 m
v = 329 m/s
= 
= 
= 391.6667 Hz
The fundamental frequency of the string is 391.67 Hz.
Answer: 1.d) The acceleration of an object is always less than the acceleration due to gravity, g (9.81m/s^-2)
2.a)acceleration decreases
Explanation:
Newton's second law:
Newton's second law states that the acceleration of an object is defined by two variables which is the total force acting on the object and the mass of that object. The acceleration is directly proportional to the net force that is applied on an object and inversely proportional to the mass of that object.
When the force applied on an object is increased so does the acceleration of an object however if the mass increase the acceleration decreases.
This can be felt when you look at the truck which usually carry heavy loads they seem to drive slow due to the load hence their acceleration is decreased by the mass that these truck carry .
