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Lymphocytes known as blastocysts make antibodies that fight infection. select the best answer from the choices provided t f

Suppose that 27 j of work is needed to stretch a spring from its natural length of 6 m to a length of 9 m. (a) how much work is needed to stretch the spring from 12 m to 14 m? j (b) how far beyond its natural length will a force of 78 n keep the spring stretched?

Which pair of quantities includes one quantity that increases as the other decreases during simple harmonic motion?