Complete the visibility of the pyramid

If the wwight of a package is multiplied by 7/10 the result is 65.8 find the weight of the package

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)

If the discriminant if a quadratic equation is 4 which statement describes the roots?