Doctors often use an electrocardiogram (EKG) reading to see if there is something wrong with how a person’s heart is beating. An EKG is a type of graph that “draws” the pumping activity of the heart. Make a claim about how graphing the heartbeat might help a doctor tell if there is a problem.

They can measure  the amount of energy gained or lost

The answer is probably c. xylem

Answer:             1.0  × 10⁻⁵ msolution:                     as we know ph is given as,                                    ph  = -log [h⁺]and,                                    [h⁺]  =  10^-ph    (1)putting value of ph in eq. 1,                                    [h⁺]  =  10⁻⁵                                    [h⁺]  =  1.0  × 10⁻⁵ m

The answer is d for this question