#### Answer

2a. 9 $\times$ t
2b. x - $\frac{1}{2}$
2c. m + 7.1
2d. 207 $\div$ n

#### Work Step by Step

2a. "product" means multiply. Therefore, the product of 9 and a number t would be 9 $\times$ t.
2b. "difference" means subtract. Therefore, the difference of a number x and $\frac{1}{2}$ would be x - $\frac{1}{2}$.
2c. "sum" means add. Therefore, the sum of a number m and 7.1 would be m + 7.1.
2d. "quotient" means divide. Therefore, the quotient of 207 and a number n would be 207 $\div$ n.