Answer:
<h2>76°</h2>
Explanation:
In projectile,
Maximum height =
and range = 
u = velocity of the body
= angle of launch
g = acceleration due to gravity
If the range equals the maximum height in an ideal projectile launch on a horizontal plane, this means;

since 

The angle at which the range equals the maximum height in an ideal projectile launch on a horizontal plane is approximately 76°
Answer:
D.
Explanation: multiply the total driving time by the total distance
The measurements used in the experiment is the amount of speed over time.
The measurement of speed is indicated along the “y” axis.
Upon viewing the graph, the highest point along the “y” axis shown is 25 m/s. This would be the maximum.
The maximum speed of the car would be 25 m/s.
(a) 764.4 N
The weight of the astronaut on Earth is given by:

where
m is the astronaut's mass
g is the acceleration due to gravity
Here we have
m = 78.0 kg
g = 9.8 m/s^2 at the Earth's surface
So the weight of the astronaut is

(b) 21.1 N
The spacecraft is located at a distance of

from the center of Earth.
The acceleration due to gravity at a generic distance r from the Earth's center is

where G is the gravitational constant and M is the Earth's mass.
We know that at a distance of r = R (at the Earth's surface) the value of g is 9.8 m/s^2, so we can write:
(1)
the acceleration due to gravity at r=6R instead will be

And substituting (1) into this formula,

So the weight of the astronaut at the spacecratf location is

C. Unbalanced. You need an unbalanced force to cause an object to move, stated by Newton's 2nd law of motion