Scala Collections - Buffers

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What does the following code print? val leaders = collection.mutable.Buffer("Reykon") leaders += "obama" println(leaders)	`ArrayBuffer(Reykon, obama)` is printed. `leaders` is a mutable list of items, commonly known as a buffer in Scala. Collections created with `List` or `collection.immutable.List` are immutable and items cannot be appended to immutable collections.
What does the following code print? val stuff = collection.mutable.Buffer("blue") stuff += 44 println(stuff)	This code throws an error. Strings are the only item that can be appended to the `stuff` buffer. You cannot append an integer to a buffer with the `scala.collection.mutable.Buffer[String]` type.
What does the following code print? val coolCreatures = collection.mutable.Buffer() coolCreatures += "spongebob" println(coolCreatures)	This code throws an error. `coolCreatures` is instantiated without any elements, so the Scala compiler assumes that all elements of the buffer will be of type `Nothing`. "spongebob" is a string (it's not of type nothing), so it cannot be added to the `coolCreatures` buffer. A type should be specified when creating an empty buffer to avoid this error. val coolCreatures = collection.mutable.Buffer[String]() coolCreatures += "spongebob" println(coolCreatures)
What does the following code print? val turtles = collection.mutable.Buffer("mikey", "leo") turtles(0) = "donny" println(turtles)	`ArrayBuffer(donny, leo)` is printed. The buffer is initially defined with mikey as the first element and leo as the second element. `turtles(0) = "donny"` mutates the `turtles` buffer, so donny is the first element.
What does the following code print? val fruits = collection.mutable.Buffer("apple", "orange") println(fruits.toList)	`List(apple, orange)` is printed. The `fruits` val is assigned to a mutable buffer. The buffer is converted to an immutable list and printed.
What does the following code print? val veggies = collection.mutable.Buffer("carrots") veggies += "peas" println(veggies.last)	`peas` is printed. The `veggies` buffer contains the string carrots and the string peas. The last element of the buffer is printed.