Explanation:

Given,
Internal diameter of the hollow sphere = 6 cm
Internal radius of the hollow sphere = 6/2 cm = 3 cm
External diameter of the hollow sphere = 10 cm
External radius of the hollow sphere = 10/2 cm = 5 cm
Volume of the hollow spherical shell = (4/3)∏×R³−r³
= (4/3)∏×5³−3³ …………………… (i)
Given the length of the solid cylinder =83 cm
Let the radius of the solid cylinder be h cm
Volume of the cylinder = ∏×r²×h
= ∏×r²×8/3 …………….. (ii)
Now equating both the above marked equations in order to obtain the radius of the cylinder
r² = 49
r =7
d= 7 * 2 =14 cm