Answer: D
Explanation: D is the most reasonable answer because it's always good to plan ahead for anything, so if you were to plan ahead for future obstacles, then you can overcome them.
Answer:
A type of telescope that does not require darkness in order to be able to use it is the refracting telescope
Explanation:
A refracting telescope consists of a lens and an eyepiece collects light which is then focused to present a magnified, bright and clear image.
The incident light on a refracting telescope is bent by refraction such that the light is focused to the focal point.
In refracting telescopes, the image is formed by bending light, that is by refraction.
The refracting telescope technology has been applied to binoculars and camera zoom lenses.
Answer:
The slope of a position-time graph represents an object’s velocity.
Explanation:
In a position-time graph, the values on the x-axis represent the time, while the values on the y-axis represent the position of the object.
Velocity is defined as the ratio between the displacement of an object and the time taken:

However, we can see that this definition corresponds to the slope of the curve in a position-time graph. In fact:
, the displacement, corresponds to the difference in position, so the difference between the values on the y-axis: 
, the time interval, corresponds to the difference in times, so the difference between the values on the x-axis: 
So, the velocity is

which corresponds to the slope of the curve.
Mass is the physical quantity