It’s timed need help ASAP!!

Steve is scuba diving near his home in maui. at one point he is 100 feet below the surface. represent this number with a negative number. if he descends another 5 feet, what negative number will represents his.

The jewelry store is having a sale. necklaces that were regularly priced at $23.50 are on sale for $18.80. what is the percentage of decrease in the price of necklaces?

Hurry if the population of of an ant hill doubles every 10 days and there are currently 100 ants living in the ant hill what will the ant population be in 20 days