To see if baldness is caused by a high protein diet, a scientist gives
one group of men a low protein diet and another group of men a high
protein diet. what is the independent variable in this experiment?
a. the amount of protein in the diets of the men
b. whether or not the men develop baldness
c. the age of the men and the amount of water they are given to drink
d. the number of men in each group

Which element is used in photosynthesis found in atmosphere and fixed by bacteria?

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

Awave has a wavelength of 15 mm and a frequency of 6 hertz. what is its speed?