Which of the following statements describes best practice when building forecast sales in a cross sheet model? Select one: Last period's sales * (1+ this period's growth assumption): because it allows CTRL [ to jump to the assumption which can easily be checked (1+ this period's growth assumption) * last period's sales: because it allows CTRL. [ to jump to the assumption which can easily be checked (1+ this period's growth assumption) * last period's sales: because this is the only mathematically correct way to build the formula Last period's sales * (1+ this period's growth assumption): because this is the only mathematically correct way to build the formula