Help? Please I need help

Lisa berry plans to rent an apartment for $1,090 per month. she estimates the annual expense will be as shown on the chart below. what is her average monthly cost?

You dug a hole that was 8 feet deep. after taking a short break, you dug down 3 more feet in the same hole. when finished digging, a tractor accidentally filled the hole with 4 feet of dirt. how deep is your hole now?

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?