求助：一道阅读题

Barron里面 TEST1 中第二篇阅读“THERMOREGULATION”! R+ P) D0 a) Z$ K0 B& V# T
20题为什么选B啊-----"Because heat is lost in water twice as fast as it is in air"+ |! M: M2 ]* l9 _$ |+ q, L6 u
原文是“The loss of heat to water occurs 50 to 100 times more rapidly than heat loss to air...”+ P2 k' v, W% [; H$ U5 a

twice=50 to 100 times more than...????# |* ]! ?: G! ?
不理解，请教～～