PLEASE HELP ASAP

SEE PICS BELOW !!!

Will mark brainliest if you answer ! the taco shop sold 198 lunches friday. this number is 3 more than 3 times the number they sold monday. let n represent the number of lunches sold monday. which equation shows an equality between two different ways of expressing the number of lunches sold on friday? a. n – 3 = 198 b. 3n – 3 = 198 c. 3n + 3 = 198 d. n + 3 = 198

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

I'm confused on this could anyone me and show me what i need to do to solve it.