Analysis of the behavior of mutableMapOf in Kotlin

Determine which elements will be printed after executing the command println(sampleMap.values).

val sampleMap = mutableMapOf("ZeroKey" to "0")
    .plus(
        "FirstKey" to "1",
    )
.apply {
        this.plus("SecondKey" to "2")
    }
println(sampleMap.values)