Select the real-world problem that could be solved using a proportion. A Sheila has 3 pens and 7 pencils. How many more pens does she need to make the number of pens and pencils she has equivalent?

B Sheila has 2 dogs and adopts 2 more. How many dogs does she have in total?

C Sheila must pay $90 for a phone and then $30 each month for service. How much will she have paid after 7 months?

D Sheila travels 90 miles in 3 hours. At this rate, how far will she travel in 7 hours?

Trish receives $450 on the first of each month. josh receives $450 on the last day of each month. both trish and josh will receive payments for next four years. at a discount rate of 9.5 percent, what is the difference in the present value of these two sets of payments?

Browning labs is testing a new growth inhibitor for a certain type of bacteria. the bacteria naturally grows exponentially each hour at a rate of 6.2%. the researchers know that the inhibitor will make the growth rate of the bacteria less than or equal to its natural growth rate. the sample currently contains 100 bacteria. the container holding the sample can hold only 300 bacteria, after which the sample will no longer grow. however, the researchers are increasing the size of the container at a constant rate allowing the container to hold 100 more bacteria each hour. they would like to determine the possible number of bacteria in the container over time. create a system of inequalities to model the situation above, and use it to determine how many of the solutions are viable.

What is the base of 1/9 to the power of 2