What should be done before measuring an unknown pH of a solution using a pH meter?

In iceland, the mid atlantic ridge runs through the center of the contry. what can you conclude about the apperence of iceland many thousands of years from now?

Ineed the answer asap. in order to be considered alive, an organism must simultaneously possess the characteristics of homeostasis, heredity, cells, reproduction, and

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction.