The blood vessels in the walls of the heart are:- a) pulmonary vessels
b) caval veins
c) coronary vessels
d) Lymph vessels

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.

well first you need the sample of the temperature and gas level. i couldnt write a hypothesis unless i had some data. i think temperature changes will effect volumes of gas because gas changed into a solid or liquid at specific temperatures.