The first and second laws apply to objects. single or multiple

no

multiple

single

the answer is to check all of them! they all apply well at least i think so!

object 2 because all the other ones are wrong

the answer is f1 and d2 because if you put equal force on those two points the beam would balance trust me on this

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west