Please answer this asap!!

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

What is 140% of 25? because i need