Sterre charges \$35$35dollar sign, 35 to file tax returns, but files for free if she only needs the easiest form. Then she donates \$2$2dollar sign, 2 to clean water projects per tax return she files. Sterre charged \$7{,}245$7,245dollar sign, 7, comma, 245 and made a donation of \$1{,}242$1,242dollar sign, 1, comma, 242 this year for the tax returns she filed.