describe the different types of severe weather that have a big impact on the biosphere and the geosphere

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Taylor wants to paint his rectangular deck that is 41 feet long and 24 feet wide. a gallon of paint covers about 350 square feet. how many gallons of paint will taylor need to cover the entire deck? round your answers to two decimal places when necessary.