The correct option is A 3 cm
Let r1=outer surface area, r2= inner surface area, length h=14
Outer curved surface area of cylinder =2×π×r1×h cm2
Inner curved surface area of cylinder =2×π×r2×h cm2
Difference between two curved surface area cylinder =2π(14)(r1−r2)=88cm2
r1−r2=1.......(1)
Volume of cylinder =π(r21−r22)h=π(r21−r22)(14)=176
r21−r22=4.....(2)
Solving, (2), we get
(r1−r2)(r1+r2)=4
1(r1+r2)=4
r1+r2=4.....(3)
From (1) and (3), we have
r1=52,r2=32
Inner diameter of cylinder =2×32=3 cm