Average speed= total distance/total time =12km/h
Answer:
12.5 m/s
Explanation:
The motion of the hammer is a free fall motion, so a uniformly accelerated motion, therefore we can use the following suvat equation:

Where, taking downward as positive direction, we have:
s = 8 m is the displacement of the hammer
u = 0 is the initial velocity (it is dropped from rest)
v is the final velocity
is the acceleration of gravity
Solving the equation for v, we find the final velocity:

So, the final speed is 12.5 m/s.
Answer:
Object A and C (Second choice)
Let's observe one by one
#A..
Kupier belt is a belt associated at Neptune outerside similar to asteroid belt
#B.
Has enough gravity to keep other objects far away from its orbit
- It's any planet or may be sun /star
No
#C
Is in orbit around the sun
#D
Is almost circular in shape