Helen: I’d expected us to have some sort of [1] device, not just stand there and count the number of [2] per minute. Not very precise, but I suppose it was good enough. But the way we [3] the amount of salt was interesting.
Colin: In the water from the rock pools?
Helen: Yeah, oh, I wanted to check the [4] we used in the lab when we analysed those [5] – was it potassium chromate and silver nitrate?
Colin: That’s right.