function addCalculatePayColumn(sheet, beginningRow) {
  sheet.insertColumnAfter(COLUMN_NUMBER.HOURLY_PAY);
  sheet.getRange(1, COLUMN_NUMBER.TOTAL_HOURS).setValue('TOTAL HOURS');
  sheet.getRange(1, COLUMN_NUMBER.CALC_PAY).setValue('WEEKLY PAY');

  // Calculates weekly total hours.
  sheet.getRange(beginningRow, COLUMN_NUMBER.TOTAL_HOURS)
      .setFormula('=ArrayFormula(D2:D+E2:E+F2:F+G2:G+H2:H)');
  // Calculates weekly pay.
  sheet.getRange(beginningRow, COLUMN_NUMBER.CALC_PAY)
      .setFormula('=ArrayFormula(I2:I * J2:J)');
}
Adds TOTAL HOURS and CALCULATE PAY columns and automatically calculates
every employee's weekly pay.

@param {Object} sheet Spreadsheet object of current sheet.
@param {Integer} beginningRow Index of beginning row.