please help me! I need to find the limit of an alternating sequence that goes 1, -1, 1, -1, ... and I know the equation is but is the limit of that going to be 1, pos or neg 1, or DNE?

Type the correct answer in the box. use numerals instead of words. if necessary, use / for the fraction bar.a city water tank holds 20 gallons of water. a technician empties 25% of the tank. how many more gallons of water must be removed from thetank so that it has 5 of the water that it started with: the technician must removemore gallons of water for the tank to have 5 of the water that it started with.