Step-by-step explanation:
The formula :
[tex]\displaystyle \rm S=A\cdot \left (1+\frac{N}{100} \right )^{\big r}[/tex]
where r is years ; N is the percentage by which we increase the price ; A is the original price
In our case :
[tex]\rm r=1 \ \ ; \ \ A=100 \ \ ; \ \ N=7,5\% \\\\ S=1000\cdot \bigg( 1+\dfrac{7,5}{100} \bigg)^1=1000\cdot 1,075=\boxed{1075\$}[/tex]
Then the monthly salary is equal to:
[tex]\dfrac{1075}{12} \approx 89,58 \$[/tex]