Plz answer mah question ;-;

Plzz hurry im being timed during times of vigorous physical activity, muscles require a constant supply of oxygen. how does the body respond to these needs? a. breathing rate and heart rate both decrease. b. breathing rate and heart rate both increase. c. heart rate decreases, but breathing rate remains stable. d. breathing rate increases, but heart rate remains stable.

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?

Mineral rich water heated by newly found oceanic crust escapes through cracks in the ocean floor called