ศักยภาพ

An Error occurred while handling another error:
yii\web\HeadersAlreadySentException: Headers already sent in /var/www/html/web/th/our-capabilities.php on line 23. in /var/www/html/vendor/yiisoft/yii2/web/Response.php:369
Stack trace:
#0 /var/www/html/vendor/yiisoft/yii2/web/Response.php(342): yii\web\Response->sendHeaders()
#1 /var/www/html/vendor/yiisoft/yii2/web/ErrorHandler.php(136): yii\web\Response->send()
#2 /var/www/html/vendor/yiisoft/yii2/base/ErrorHandler.php(152): yii\web\ErrorHandler->renderException(Object(DivisionByZeroError))
#3 [internal function]: yii\base\ErrorHandler->handleException(Object(DivisionByZeroError))
#4 {main}
Previous exception:
yii\base\ErrorException: Undefined variable $col in /var/www/html/web/th/our-capabilities.php:171
Stack trace:
#0 /var/www/html/web/th/our-capabilities.php(171): yii\base\ErrorHandler->handleError(2, 'Undefined varia...', '/var/www/html/w...', 171)
#1 {main}

Next DivisionByZeroError: Modulo by zero in /var/www/html/web/th/our-capabilities.php:171
Stack trace:
#0 {main}