Simplify the expression by using the properties of rational exponents. Write the final answer using positive exponents only.

Acertain population of bacteria demonstrates exponential growth doubles in size every 4 days. how long will it take the population to triple in size?

Sandy is ordering bread rolls for her party,she wants 3/5 of the rolls to be whole wheat. what other factions can represent part of the rolls that will be whole wheat? shade the models to show your work.

You are at a restaurant and owe $56.20 for your meal. you want to leave an 18% tip. approximately how much is your tip?