#### Answer

a. 27
b. 7
c. 17
d. The fraction bar groups the number on top (numerator) and the number on the bottom (denominator) with a divide operation.

#### Work Step by Step

a. $ 5 \times 7 - 4^2 \div 2 = 35 - 16 \div 2 = 35 - 8 = 27$
b. $12 - 25 \div 5 = 12 - 5 = 7$
c. $\frac{4 + 3^4}{7 - 2} = \frac{4 + 81}{5} = \frac{85}{5} = 17$
d. The fraction bar is a grouping symbol because it groups together the number above it (numerator) and the number below it (denominator). For example, $\frac{8}{2}$ is grouping the 8 and the 2 with a divide operation (8 / 2).