please answer the following questions: (keep it brief, a few sentences maximum)

1. how do we calculate the between-groups sum of measures?

2. What are Cohen's conventions for interpreting effect size using R²?

3. Find the incorrectly used symbol or symbols in each of the following statements or formulas. For each statement or formula, (i) state which symbol(s) is/are used incorrectly, (ii) explain why the symbol(s) in the original statement is/are incorrect, and (iii) state which symbol(s) should be used:

a. SS_within = (X-M)

. b. F =t