Can someone please help me with these four problems I do not know how to solve them

Identify the polynomial. a2b - cd3 a. monomial b. binomial c. trinomial d. four-term polynomial e. five-term polynomial

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 (%)

In the figure, triangle aob and triangle boc form a linear pair ,find the measure of x