Answer:
The vision becomes blurred due to the refractive defects of the eye. There are mainly three common refractive defects of vision. These are (i) myopia or near-sightedness, (ii) Hypermetropia or far – sightedness, and (iii) Presbyopia. These defects can be corrected by the use of suitable spherical lenses.
Answer:

Explanation:
From the question we are told that:
Height of window 
Height of window off the ground 
Time to fall and drop
Generally the Newton's equation motion is mathematically given by

Where



Generally the Newton's equation motion is mathematically given by

Where





Therefore the ball’s initial speed

Answer:
![g_{moon}=1.67 [m/s^{2} ]](https://tex.z-dn.net/?f=g_%7Bmoon%7D%3D1.67%20%5Bm%2Fs%5E%7B2%7D%20%5D)
Explanation:
The weight of some mass is defined as the product of mass by gravitational acceleration. In this way using the following formula we can find the weight.

where:
w = weight [N]
m = mass = 0.06 [kg]
g = gravity acceleration = 10 [N/kg]
Therefore:
![w=0.06*10\\w=0.6[N]](https://tex.z-dn.net/?f=w%3D0.06%2A10%5C%5Cw%3D0.6%5BN%5D)
By Hooke's law we know that the force in a spring can be calculated by means of the following expression.

where:
k = spring constant [N/m]
x = deformed distance = 6 [cm] = 0.06 [m]
We can find the spring constant.
![k= F/x\\k=0.6/0.06\\k=10 [N/m]](https://tex.z-dn.net/?f=k%3D%20F%2Fx%5C%5Ck%3D0.6%2F0.06%5C%5Ck%3D10%20%5BN%2Fm%5D)
Since we use the same spring on the moon and the same mass, the constant of the spring does not change, the same goes for the mass.
![F_{moon}=k*0.01\\F = 10*0.01\\F=0.1[N]](https://tex.z-dn.net/?f=F_%7Bmoon%7D%3Dk%2A0.01%5C%5CF%20%3D%2010%2A0.01%5C%5CF%3D0.1%5BN%5D)
Since this force is equal to the weight, we can now determine the gravitational acceleration.
![F=m*g_{moon}\\g=F/m\\g = 0.1/0.06\\g_{moon} = 1.67[m/s^{2} ]](https://tex.z-dn.net/?f=F%3Dm%2Ag_%7Bmoon%7D%5C%5Cg%3DF%2Fm%5C%5Cg%20%3D%200.1%2F0.06%5C%5Cg_%7Bmoon%7D%20%3D%201.67%5Bm%2Fs%5E%7B2%7D%20%5D)
The answer is C hope it helped