For a moving object, the force acting on the object varies directly with the object's acceleration. When a force of 21 N acts on a certain object, the acceleration of the object is 3 m/s?. If the acceleration of the object becomes 2 m/s?, what is the force?

a is the right answer

first the equation needs to be simplified. so the equation would now look like:   52-24+11

then you multiply.

and when you multiply, you will get the answer of 39.  

the answer is 3.54 g/cm^3

step-by-step explanation:

d=mass/volume therefore d= 46/13 which is a simple division equation.