A student made the table shown to list some contact and non-contact forces. Examples of Forces
Contact Forces Non-Contact Forces
The force exerted by a stretched spring The force applied by Earth and sun on each other
The electrical force exerted by a positive charge on a negative charge Magnetic attraction between two magnets

Which statement best explains why the table is incorrect?
Spring force is a force acting at a distance.
Electrical force is not a contact force.
Gravitational force can act between planets and sun only when they are in contact.
Magnetic attraction is a contact force.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

layer 3 is younger than layer 6.

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.