Answer:
, where the minus indicates the direction is opposite to that of the throw.
Step-by-step explanation:
a)
Since MKS stands for meter-kilogram-second and we know that:



We can write that:



These are conversion factors, equal to 1, so multiplying our results by them won't change their value, only their units.
So we have that:



b)
Newton's 2nd Law tells us that F=ma, and the definition of acceleration is
, so we have:

Taking the throw direction as the positive one, for our values we have:
