Saturday Mac riddles 30

Here are this weekend’s riddles to entertain you through family time, shopping and recreation.

1: I can come dry or floating, but here I’m mainly used for launching. What am I?

2: 1, -273.15, e, SUM(B4:B9).

3: For which language did Apple implement its first class library for Mac application development?

I will post the answers first thing on Monday morning.

Please don’t post your answers as comments here: it spoils it for others.