I believe it is the first one
Answer:
The velocity is 
Explanation:
From the question we are told that
The mass of the bullet is 
The initial speed of the bullet is 
The mass of the target is 
The initial velocity of target is 
The final velocity of the bullet is is 
Generally according to the law of momentum conservation we have that

=> 
=> 
Answer:D
Explanation: i found the answer in an answer key!
Answer:
The same pendulum could be adjusted to have the same period, in the equator must have a length of 3.949m.
Explanation:
Tnp= 4 sec
gnp= 9.83 m/sec²
Lnp= 3.97m
Tequ= 4 sec
gequ= 9.78 m/sec²
Lequ=?
Lequ= (Lnp* gequ) / gnp
Lequ= 3.949 m