Answer:
the no. of activities supply in a cahin like in the figuration wise they supply the chain
Answer:
17.799°
Explanation:
When the bullet hits the block at that time the momentum is conserved
So, initial momentum = final momentum

So 

Now energy is also conserved
So 

B is the answer I believe so
Explanation:
Yes Diesel engine have problem of knocking.
We know that knocking is phenomenon in which suddenly large amount of power generates this large amount of power will cause the failure of diesel engine.
Actually when one set of fuel inject inside the cylinder to burn with already compressed air (in general up to 10-15 bar) then this fuel does not burn complete and accumulate inside the cylinder.After that second set of fuel inject inside the cylinder then that one set of fuel burns with second set of fuel and produces large amount of sudden power for engine and causes the breaks in the crank or connecting rod of engine.it leads to damage the engine.