The battery in a portable music player is guaranteed to last 17 hours without charging if it is used with headphones and 3 hours if it is used with speakers. If you use headphones and speakers for equal amounts of time, how many minutes will a fully charged battery last?

Need to finish my juan wants to build a greenhouse in his back yard. he needs to maximize the ratio of floor area to structure volume in order to provide the most room for plants while minimizing the area to be heated. find the description of the structure that best meets juan’s criteria. a.) a hemisphere with a diameter of 12 feet b.) a cube with a side length of 12 feet c.) a cone with a diameter of 12 feet and a height of 10 feet d.) a square pyramid with a base side length of 12 feet and a height of 9 feet