Answer:
F test statistic will be used as per explained procedure. 
Explanation:
Let XL, XT, XJ be mean averages of rats with Linda, Tuan, Javier respectively.
Null Hypothesis [H0] : XL = XT = XJ 
Alternate Hypothesis [H1] : Either of XL, XT or XJ are unequal 
F test will be used to test the significance of difference between three groups. 
If critical p value corresponding to significance level (10%) < calculated p value : Null Hypothesis is rejected. This means that means are unequal 
If critical p value corresponding to significance level (10%) > calculated p value : Null Hypothesis is not rejected. This means that means are equal