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An athlete holds a 7.5-kg shot put in his hand with his lower arm horizontal, as shown in the figure. His lower arm has a mass of 2.8 kg and its center of gravity (or center of mass) is 12 cm from the elbow-joint pivot. How much force must the extensor muscle (which is  M in the figure) in the upper arm exert on the lower arm? 

As shown in the figure, two blocks are connected by a light string that passes over a frictionless pulley having a moment of inertia of 0.0040 kg ∙ m2 and diameter 10 cm. The coefficient of kinetic friction between the tabletop and the upper block is 0.30. The blocks are released from rest, and the string does not slip on the pulley. How fast is the upper block moving when the lower one has fallen 0.60 m? 

The curved section of a horizontal highway is a circular unbanked arc of radius 740 m.  If the coefficient of static friction between this roadway and typical tires is 0.40, what would be the maximum safe driving speed for this horizontal curved section of highway?

What is the SI unit of momentum?

A [answer1] brand is a method of identification that kills the pigment portion of a hair follicle if done correctly, while a [answer2] brand kills the whole hair follicle. Use one word for each answer. 

ATP synthase uses a proton (H+) gradient to generate ATP.

A zygote is diploid and forms after fertilization.

The electron transport chain is located in the inner mitochondrial membrane in eukaryotic cells.

  1. Identify two biological mechanisms that contribute to genetic diversity in animals. (2 points) 2. Explain how they do so. (2 points)

For the DNA sequence ACCGGGATACG, the complementary DNA sequence would be: