A tank is full of water. Find the work (in J) required to pump the water out of the spout. (Use 9.8 m/s² for g. Use 1,000 kg/m³ as the density of water. Round your answer to the nearest whole number.) × J 3 m 9 m According to Hooke's Law, the force required to hold the spring stretched x m beyond its natural length is given by f(x) = kx, where k is the spring constant. Suppose that 4 J of work is needed to stretch a spring from its natural length of 34 cm to a length of 48 cm. Find the exact value of k, in N/m. k = 408.16 N/m (a) How much work (in J) is needed to stretch the spring from 39 cm to 44 cm? (Round your answer to two decimal places.) 1.53 J (b) How far beyond its natural length (in cm) will a force of 50 N keep the spring stretched? (Round your answer one decimal place.) 12.3 cm