The atomic number of krypton (kr) is 36, and its mass number is 84. how many neutrons does it have?
a) 18
b) 36
c) 48
d) 72

Asquare kilometer of forest has 200 deer. what is the term that is used to describe this number?

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.

What does the hardy-weinberg principle relate to? a. chances of survival of an organism b. frequency of alleles in a population c. natural selection in a species d. causes of evolution among organisms