Look at the conversation btwn Alvin and Ken
Alvin: Why does my towel still have tomato stain on it after I washed it with a cleaning agent A? can remove the stain effectively.
Based on the conversation, identify cleaning agent A & B by planning a laboratory experiment to study the effectiveness of the agents in hard water.
ALL THE PLANNING SHOULD INCLUDE THE FOLLOWING ASPECTS:
(1) Problem statement
(2) All the variables
(3) Statement of the hypothesis
(4) List of materials and apparatus used
(5) Procedure for the experiment
(6) Tabulation of data
Ken: I'm using cleaning agent B. It
The '...' is Ken: I'm using cleaning agent B. It~'
Thanks. Here is the correct one.