Please help me with this assignment!

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

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field

Micheal is 4 times as old as brandon and is also 27 years older than brandon. how old is micheal