Which if the following is a base
a) substance d contains carbon hydrogen oxygen and nitrogen
b) substance b gives off oh- ions that combine with h+ ions when dissolved in water
c) substance c is formed drom the reaction of an acid and base
d) substance a gives off h+ ions that combine with oh- ions when dissolved in water

The image shows ekgs of a person with normal heart waves and of a person having tachycardia. based on this image, what kind of condition is tachycardia? a. the heart beats abnormally fast. b. the heart beats abnormally slow. c. the right atrium of the heart stops working. d. the left ventricle pumps less blood to the aorta.

What are the responsibilities of the region of the brain highlighted below? =+= will rate brainiest =+=

The chemical form of energy that is useable by the cell to do work