I need helpp guys i hope i get correct answers because i do NOT get this lol

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

Hurry if the population of of an ant hill doubles every 10 days and there are currently 100 ants living in the ant hill what will the ant population be in 20 days

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.