Let's call

the mass of the glider and

the total mass of the seven washers hanging from the string.
The net force on the system is given by the weight of the hanging washers:

For Newton's second law, this net force is equal to the product between the total mass of the system (which is

) and the acceleration a:

So, if we equalize the two equations, we get

and from this we can find the acceleration:
Answer:
The answer to your question is 636.6 ft
Explanation:
Data
base = 425 ft
angle = 39°
See the picture below
1.- Divide the triangle to get two right triangles.
Now the superior angle will measure 19.5° and the opposite side will measure 212.5 ft
2.- Use the trigonometric function sine to find the hypotenuse
sin 19.5 = 212.5/hyp
solve for hyp
hyp = 212.5 / sin 19.5
Result
hyp = 212.5/ 0.333
hyp = 636.6 ft
I don’t even know I’m so dumb.
It evaporates into a vapor
~~~hope this helps~~~
~~have a beautiful day~~
~davatar~