题目

A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度) of yellow makes it less difficult for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.The study was led by Prof Ho. To test whether there was a relationship between the color of 我们知道水既普通又宝贵，日常生活、工农业生产和科学研究都离不开水。下图表示通电分解水的简易实验装置。回答下列问题： ①B量筒中产生的气体是_________；②如果用VA和VB分别表示A量筒和B量筒中生成气体的体积，则VA∶VB约等于_________； ③如果该实验中产生氧气32g，需要电解水_________g。