<span>You could easily define it this way. This would be valid. But for most of history it was unclear when a baby was conceived, so it would be silly for someone to say their baby was 9 months old when it was actually born at only 8.5 months. Days of conception similarly would not be a good substitute for birthdays because no one would know them. Then in general it was much easier to mark someone's age as when they came into the world as an independent being, and this tradition is far too entrenched (and simple and easy to handle and universal for people in poor countries etc) to think we would at all gain from now finding exactly the date of conception and counting age from that point.</span>
Answer:In terms of an equation, the momentum of an object is equal to the mass of the object times the velocity of the object. where m is the mass and v is the velocity. The equation illustrates that momentum is directly proportional to an object's mass and directly proportional to the object's velocity.
Explanation:
The answer is B hope this helps
C. Forces are always in pairs
Answer:
the third stage was 480 km long
Explanation:
Stage 1:
Time = 1 hours
Speed = 80km
Stage 2:
Time = 2 hours
Speed = 200km
Stage 3:
Time = 4 hours
Let the Distance at the stage 3 be x
Average speed of the train route = 100 km/h
So
Lets find the speed at stage 1
Speed = 
Speed = 
Speed 1= 80 km/hr
The speed at stage 2
Speed =
Speed = 
Speed 2 = 100 km/hr
The speed at stage 3
Speed =
Speed = 
Speed 3 =
we kow that average is ,
x = 480
