下列各项中，加点的词语使用恰当的一项是（ ）

Please tell him ___me a call as soon as he___home from work.

Global warming is a big _______ for all and it’simportant to raise awareness about climate change

Being young means having all kinds of possibilities, so you should challenge your limits and go ______ your boundaries

Two men, starting at the same point, walk in opposite directions for 4 meters, turn left and walk another 3 meters. What is the distance between them