Answer/Explanation:
The weight of an object is defined as the force that is exerted due to the gravitational force.
Mathematically, it can be written as :
W = m g
Where
m is the mass of the object
g is the acceleration due to gravity
Also,
We know that the value of g varies with respect to the location. At the equator, the value of g is less as compared to the poles.
The feature of an object that affects its weight are :
Mass of the object
Location of the object
How much force Earth exerts on the object
Here it is given that speed of migrating Robin is 12 m/s relative to air
so we can say that
North
so it will be
Let North direction is along Y axis and East direction is along X axis

also it is given that speed of air is 6.7 m/s relative to ground

now as we know by the concept of relative motion


now by rearranging the terms


now we need to find the speed of Robin which means we need to find the magnitude of its velocity which we found above
So here we will say


so the net speed of Robin with respect to ground will be 13.7 m/s
True because the speed of a mass can change it's gravitational potential energy in the gravitational field of another massive object.
<span>A pliable sheetlike structure acting as a boundary, lining, or partition in an organism.</span>