An infinite grounded conducting tube of radius 10cm is centered on the z axis. A concentric charged tube of radius 6 cm has a surface charge density of 24 uC/m2. A 1m long section of the charged tube is compressed to change its radius to 3 cm. It remains a concentric hollow tube with the same total charge. The charge per unit length remains the same, but the surface charge density had increased. How much work must be done to compress the 1m long section from a radius of 6cm to 3cm.