Yep. 'a', 'b', and 'c' are all accurate.
Actually, 'b' doesn't go far enough. Light is not only "faster than
anything else we know of", we now know that it's impossible for
anything with mass to ever hit that speed, so we can just quit looking.
Because tropical moist forests are used for agricultural, the thin soil cannot support continuous cropping, while deciduous forests can regrow quickly.
Since the object is in equilibrium, then the sum of the forces acting on it is zero. You must do the sum of forces for the component "y" and for the component "x". From there you clear the components of the third force. Then you must find the direction and magnitude.
The result is a force of 85.01N at 74.30 degrees from the x axis. Attached solution.
For those seeking for the answer, its a source of electrical energy.