Acylindrical rain barrel with a diameter of 3.5 feet and a height of 5.5 feet is filled to a height of 0.5 feet. how many more gallons of water can the barrel hold? round your answer to the nearest whole number. (1 ft3≈7.5 gal)

The volume of the barrel is given by:
 V1 = (pi) * (r ^ 2) * (h)
 Where,
 r: barrel radio
 h: height of the barrel
 Substituting values we have:
 V1 = (3.14) * ((3.5 / 2) ^ 2) * (5.5)
 V1 = 52.89 feet ^ 3
 The volume of the barrel up to a height of 0.5 feet is given by:
 V2 = (3.14) * ((3.5 / 2) ^ 2) * (0.5)
 V2 = 4.81 feet ^ 3
 Subtracting both volumes we have:
 V1-V2 = 52.89 - 4.81
 V1-V2 = 48.08 feet ^ 3
 In gallons we have:
 V1-V2 = (48.08) * (7.5)
 V1-V2 = 360.6 gallons
 Round to the nearest whole number:
 V1-V2 = 361 gallons
 
 the barrel can hold 361 more gallons