Yes it is a exothermic reaction.
Troposphere has most of our clouds temperature etc
Answer:
The atomic radius increases down the group because more shell are added
Explanation:
Al >B
Na>Al
S>O
O>F
Br>Cl
Mg>Ca
For 100m Race ,
displacement = distance covered .
divide the above equation by time t (assuming it takes t time to complete 100m race),
we get,
velocity = speed.
and for 400m race 1 lap is completed this means that racer's initial and final position coincide (or same) hence,
displacement = 0,
distance ≠0=400m.
=> displacement ≠distance.
=> velocity ≠ speed.
-3 is the answer your looking for