Use cylindrical gaussian surfaces, coaxial with the charged cylinders.
Use a cylindrical gaussian surface, coaxial with the charged cylinder. Remember that the charge enclosed when r < R is only a fraction of the total charge. Set up an integral to evaluate the enclosed charge.
One word -- superposition!
Use a spherical gaussian surface, centered about the center of the charge sphere. Remember that only a fraction of the total charge is enclosed by the gaussian surface when r < R. Set up an integral to evaluate the enclosed charge and the total charge.