There are 4 remaining bits, so there are 16 (14 usable) hosts per subnet. The increment of the subnet addresses is 16 (x.y.z.0/28, x.y.z.16/28, x.y.z.32/28, x.y.z.48/28 etc.) so 188.8.131.52, 184.108.40.206 and 220.127.116.11 are broadcast addresses. If you add 1 to the final octet of each, 16 is a divisor.
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