<h2>ANSWER: </h2><h2>_____________________________________</h2><h2>TYPES OF CHEMICAL REACTIONS:</h2>
There are two types of Reactions,
<h3>
Endothermic Reactions: </h3>
Endothermic reactions are the type chemical reaction in which the reactants absorb heat energy from the surroundings. The energy of reactants is more than the energy of product
<h3>Exothermic Reactions: </h3>
Exothermic reactions are the type of chemical reactions in which release of energy takes place in the form of heat or light. In an exothermic reaction, energy is released. The energy of the products is less than the energy of the reactants.
<h2>_____________________________________</h2><h3 /><h3>In Question number 5,</h3>
The key word is "RELEASE". The reaction in which energy is released is the Exothermic reaction thus the Option B that is EXOTHERMIC REACTION is correct.
<h2>_____________________________________</h2><h3 /><h3>In Question number 6</h3>
It is asking that which process stores the energy that means it is asking which process undergoes endothermic reaction. The answer is Option C that is PHOTOSYNTHESIS is correct.
<h3>__________________________________________________</h3><h3>WHY PHOTOSYNTHESIS?</h3>
Because, sunlight is being absorbed during the reaction and according to the definition of endothermic reaction if heat is being absorbed it is termed as an endothermic reaction.
<h3>__________________________________________________</h3><h3 /><h3 />
Answer:
This is because when the pedal sprocket arms are in the horizontal position, it is perpendicular to the applied force, and the angle between the applied force and the pedal sprocket arms is 90⁰.
Also, when the pedal sprocket arms are in the vertical position, it is parallel to the applied force, and the angle between the applied force and the pedal sprocket arms is 0⁰.
Explanation:
τ = r×F×sinθ
where;
τ is the torque produced
r is the radius of the pedal sprocket arms
F is the applied force
θ is the angle between the applied force and the pedal sprocket arms
Maximum torque depends on the value of θ,
when the pedal sprocket arms are in the horizontal position, it is perpendicular to the applied force, and the angle between the applied force and the pedal sprocket arms is 90⁰.
τ = r×F×sin90⁰ = τ = r×F(1) = Fr (maximum value of torque)
Also, when the pedal sprocket arms are in the vertical position, it is parallel to the applied force, and the angle between the applied force and the pedal sprocket arms is 0⁰.
τ = r×F×sin0⁰ = τ = r×F(0) = 0 (torque is zero).
The answer is commensalism because commensalism is a relationship where an organism is benefitted and the other is neither benefitted nor harmed. The barnacle is being benefited and the whale is not being benefited or harmed.
Answer:

Explanation:
Since the system is in international space station
so here we can say that net force on the system is zero here
so Force by the astronaut on the space station = Force due to space station on boy
so here we know that
mass of boy = 70 kg
acceleration of boy = 
now we know that


now for the space station will be same as above force



