Suppose an ISP has got a block that begins with $71\mathrm{.}94.\frac{0\mathrm{.}0}{15}.$ The $"/15"$ on the end of the block address tells us that this is a block of addresses where the first $15$ bits are the network ID and the last $17$ the host ID$.$ The ISP reserves half of the block for future allocation while meeting the following immediate requests from his customers $($including ISPs$)$

$32$ Customers need block of $510$ addresses each

$64$ Customers need block of $254$ addresses each

$128$ Customers need block of $126$ addresses each

$256$ Customers need block of $62$ addresses each

Design a subnetting Strategy to minimise the waste of IP addresses.