= Solution
The standard output is \b[three lines]:
``
A
2.3
B
``
This is program output, excluding any interactive interpreter's display of returned values. The calls `a.m(1)` and `b.m(5.6)` compute squares without printing. In `A`, the concrete `m(Int)` wins over the <generic method> at argument `1`; the string and `2.3` use `m[T]` and print their arguments.
For `b: B[Any]`, the class <type parameter> has already become `Any`, so the two alternatives are `m(Any)` and `m(Double)`, rather than a method with its own freely inferred <type parameter>. The `Double` alternative is more specific. It accepts `4` by <numeric widening>, so `b.m(4)` computes `16.0` without printing; `b.m("B")` prints `B`; `b.m(5.6)` computes a square without printing. These are applications of the <Scala> 2.11 <method overloading> rules, with the arithmetic return values discarded in statement position.https://www.scala-lang.org/files/archive/spec/2.11/06-expressions.html#overloading-resolution[Scala 2.11 Language Specification, §6.26.3, overload applicability and specificity]{ref}
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