2025年10月国际A卷 · 第 20 题

2025年10月国际A卷 · 原库模块 2 · Q20 原库参考解析

The table shows the volume of two similar solids, right circular cylinder A and right circular cylinder B. The radius of right circular cylinder A is 7 units. The surface area of right circular cylinder A is \( kπ \) square units, and the surface area of right circular cylinder B is \( nπ \) square units, where k and n  are constants. What is the value of \( n−k \)? (The surface area of a right circular cylinder with radius r  and height h is \( 2πr^{2}+2πrh \).)