This book addresses largely three-dimensional problems. Scattering problems for bodies, small in comparison with the wavelength, are reduced to static problems. Complex variable methods (conformal mappings) for solving static two-dimensional problems have been widely discussed in the literature. The problems solvable in closed form are collected in [13], [33], [43], [58], [143], [71], [73]. The method of separation of variables has been used to solve the static problems for ellipsoids and its limiting forms (disks, needles), for a half-plane, wedge, plane with an elliptical aperture, hyperboloid of revolution, parabaloid of revolution, cone, thin spherical shell, spherical segment, two conducting spheres, and some other problems. Electrostatic fields in a flaky (layered) medium with parallel and sectorial boundaries have been studied [33], [143]. Some of the problems were solved in closed form using integral equations, e.g., the problems for a disk, spherical shell, plane with a circular hole, etc. Wiener-Hopf, dual, and singular integral equations were used [33], [143], [76], [164]. Electrostatic problems for a finite circular hollow cylinder (tube) were studied in [158] by numerical methods. The capacitance per unit length of the tube and the polarizability of the tube were calculated. The authors reduced the integral equation for the surface charge to an infinite system of linear algebraic equations and solved the truncated system on a computer. Their method depends heavily on the particular geometry of the problem and does not allow one to handle any local perturbations of the shape of the tube. In [68] the variational methods of...