Find the value of a1 for an infinite geometric series with s=-45 and r=-1/ get -5 but its saying its wrong. idk how

You will get 25 points an image of a rectangular prism is shown below: part a: a cross section of the prism is cut with a plane parallel to the base. what is the name of the shape created by the cross section? explain your answer. (5 points) part b: if a cross section of the prism is cut perpendicular to the base, what would be the shape of the resulting cross section? explain your answer. (5 points)

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Adam plans to choose a video game from the section of the store where everything is 75% off. he writes the expression d-0.75d to find the sale price of the game if the original price is d dollars. gena correctly writes another expression, 0.25d, that will also find the sale price of the game if the original price is d dollars. use the drop down menus to explain each part of adams and rena's expression