Double replacement i believe
Answer;
A) Stage 1: Chlorophyll captures light energy. Stage 2: Light energy is converted to chemical energy.
Explanation;
-Photosynthesis is the process by which green plants use energy from the sun, water and carbon dioxide to make organic compounds such as simple sugars together with release of oxygen.
-The process occurs in tow stages; light-dependent stage and light independent stage. During light dependent stage, chlorophyll absorbs sunlight and uses it to split water molecules into hydrogen ions and oxygen atoms. In the light independent stage carbon (iv) dioxide is fixed and the result is organic compound; the light energy is converted to chemical energy.
Answer:

Explanation:
Hello,
In this case, we need to remember that for the required time for a radioactive nuclide as radium-226 to decrease to one half its initial amount we are talking about its half-life. Furthermore, the amount of remaining radioactive material as a function of the half-lives is computed as follows:

Therefore, for an initial amount of 100 mg with a half-life of 1590 years, after 1000 years, we have:

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18. a) The materials that are in contact. The two materials and the nature of their surfaces. ...
b) The force pushing the two surfaces together. Pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other.
19. the quantity of motion of a moving body, measured as a product of its mass and velocity.
20. According to Newton's third law of motion, action force is equal to reaction but acts on two different bodies and in opposite directions. When a horse pushes the ground, the ground reacts and exerts a force on the horse in the forward direction. This force is able to overcome friction force of the cart and it moves.
21. The mass of an object is a measure of the object's inertial property, or the amount of matter it contains. The weight of an object is a measure of the force exerted on the object by gravity, or the force needed to support it. The pull of gravity on the earth gives an object a downward acceleration of about 9.8 m/s2.
22. R12. Mass is more fundamental because it is an intrinsic property of an object. Weight varies with location depending upon the acceleration due to gravity eg. for a mass m = 10kg on Earth it`s weight is W = mg = 10 x 10 = 100N.