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The energy and the spring constant are related by ; E=1/2KX^2.......(a), where x,is the spring constant, so plugging in the values; 8.0 *10^-34=1/2*K*X^2 .........(1), since the displacement x is not given. We assume that when a quantum system is in equlibrium the gravitational force =spring force meaning: mg=kx .........(2), solving for X in equation (2) and plugging in one (1) and using the givens :

K=(mg)^2/(2*8.0*10^-34),........(3) note the factor 2 is from the equation (a). The answer is ~K=1.35*10^36

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