4meonly wrote:OA is
C but I got
B

Let me try to explain...
let AB=b and BO=h. Therefore, the perimeter is, b+h+10.
From the first statement, we find out that since B is the mid point of AC, triangle ABC is a right-angled triangle. But, we cannot tell what the base and height are, which is required to figure out the perimeter.
all we can tell is b^2 + h^2 = 100
Therefore, insufficient.
From the second statement, we can say that b*h = 48. but, we do not know if b is perpendicular to h or not. Also, we do not know the value of (b+h). So, insufficient.
From both statements together, since we know the value of b*h and we also know b is perpendicular to h, we can find out the value of (b+h) to be equal to 14. So, the perimeter is b+h+10 = 14+10 = 24.
Hence, the answer is C.