(20 poinst and brainliest for best)
a dress that normally sells for $72 is on sale for $45. what is
the percent decrease in the price?

What is the number 321,000,000 in scientific notation? also what is the number? ?

Need asap. solve for the following inequality

David estimated he had about 20 fish in his pond. a year later, there were about 1.5 times as many fish. the year after that, the number of fish increased by a factor of 1.5 again. the number of fish is modeled by f(x)=20(1.5)^x. create a question you could ask that could be answered only by graphing or using a logarithm.