Kelli has $450 in a savings account. She wants to have at least $300 at the end of the summer. She withdraws $15 per week. How many weeks can Kelli withdraw money from her account

The krasnapolski is a top-of-the-line hotel in amsterdam, the netherlands. among their many services, they rent bicycles to guests. the bicycle checkout is open 24 hours per day 7 days per week and has 50 bicycles on hand. on average, 10 guests request a bicycle each day, arriving completely randomly at all times of the day during the spring and summer seasons. guests keep bicycles for four days on average, with a standard deviation of two days. how long does a guest on average have to wait for a bike? a. approximately 24 hours b. approximately 0.033 hours c. approximately 4 days d. approximately 47 minutes

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

What is the similarity ratio of a cube with volume 729m^3 to a cube with volume 3375 m^3