Wild ducks often spend a lot of their time in the water. The ducks have special structures, called , that improve the ducks' ability to swim.

Webbed feet

Explanation:

Ducks are a species of birds that usually spend most of their time in water. The feed and breed around waterbodies such as lakes, marshes, rivers and streams. To enable them thrive in their water environment, ducks have developed several structures. One of such structure is the webbed design of their feet. This design enables them to swim much better and faster in order to hunt for food or to avoid predators. Recent research have discovered that while swimming, ducks push both backward and downward with each stroke of their webbed feet. This provides a combination of lift and thrust, assisting them to move through water with greater speed and efficiency.

Other important features of the duck include the preen gland (uropyial gland) which produces oil that keeps the ducks feather from getting wet while in water, thus assisting them to float; hollow bones which makes them lightweight, etc.

the focus of lesson 1 is newton's first law of motion - sometimes referred to as the law of inertia. newton's first law of motion is often stated as. an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

explanation:

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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