Answer: C. The sign of the enthalpy of the reaction reverses.
Explanation: Enthalpy of a reaction is the net heat absorbed or released during a chemical reaction.It is represented by 
. It is negative for exothermic reactions in which heat is released and is positive for endothermic reactions in which heat is absorbed.
When a chemical reaction is reversed the heat of the reaction changes its sign.
The decomposition of calcium carbonate is an endothermic reaction as heat is required to break the bonds and thus energy is absorbed.
When the reaction is reversed, the reaction becomes exothermic as now bonds are getting formed and energy is released.
Answer: a. control starfish populations
The Harlequin shrimp is a native of salt water marine environment. It is found near the coral reefs in the Pacific and Indian Oceans. It drives nutrition by eating starfish. They are very skilled in obtaining the starfish as a prey. They firstly eat the tube feet and soft tissues and then the central disk is feeded upon.
<span>A person who is ill with fever will experience an increased basal metabolic rate. The body’s metabolism contains all of the chemical and biological process needed for the conversion of food into energy and the use of it like digestion and excretion. So when we become sick, the metabolism speeds up to fight the illness.
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Answer:
Light energy (sunlight)
By autotrophs
As they make food from it
The columnar joints can be defined as the structures formed in basalt. The are composed of columns that are separated by the cracks or fractures that occurs in the rocks when it contracts when it is cooling down. Basalt are volcanic igneous rocks formed from the erupted lava. The lava cools down after its eruption. When it cools, it starts contracting, which leads to the fractures and cracks. The contraction causes the formation of the columns mostly in the hexagonal shapes. This leads to the formation of the geometrical columnar joints.
