Jeffrey wants to lose weight by using caffeine to help with exercise. He asks himself, Which
caffeine drink will raise the heart rate the most?"
He tries to test this out by comparing the heart
rates of his neighbors, 3 brothers who are
triplets. One of the brothers drinks Pepsi,
another drinks a double shot of espresso (which
is coffee with twice the normal amount of
caffeine) and a third brother drinks only water for
comparison.
Jeffrey finds out that the triplet with the double
shot of espresso had the highest heart rate.
4. What is the independent variable for this experiment?

The kobe habor wharfs where the center of japanese exports to other countries. it had 200 wharfs before the earthquake. how many wharfs remained undamaged after the earthquake? a. 130 wharfts b. 3 wharfs c. 30 wharfs

Zoe decided to measure the hand length of each of her classmates. first she marked a line across each student's wrist and lined up a ruler from this mark to the top of the middle finger to measure the length. then she recorded the measurements in the table below. marla did this the same way for each classmate, and then zoe used this ruler to measure each straight line and record the data below. this data is invalid. what is the most likely reason why it is invalid? the ruler is marked in centimeters, but zoe recorded data in inches. the range of lengths is too wide, so zoe must have misread the ruler. marla’s complicated measuring procedure was overly confusing. marla could have been inconsistent while drawing outlines of fingers.

The tubes transporting minerals and water upward are called ?