Answer:
A
Explanation:
I believe the answer is A because conservation tillage reduces erosion & runoff but I'm not 100% sure.
<span>A scientific law describes repeated observations under a given set of conditions. These laws are not too specific, and they imply a casual relationship. These laws do not explain why something occurs, they merely state that something will occur if the given conditions are met. Therefore, the formation of a scientific law is a result of repeated observations. An example is Newton's first law of motion, which gives certain conditions for an object, such as no force acting on it, and then describes what the object will do in that situation, that is, remain in motion or remain stationary.</span>
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This I think definitely will help :)
Ans.
Steroids are defined as active organic bio-molecules, having four rings with a specific molecular configuration. Steroids play role in two major functions: as hormones or signaling molecules and as structural components of plasma membrane.
Examples of steroid hormones are estrogen, progesterone, and cortisol. Thus, the correct answer is 'option b). they serve as chemical messengers.'