Aristotle developed the first classification system and divided all known organisms into two groups:
plants and animals. He further divided the
animals into three smaller subgroups: land
dwellers, water dwellers, and air dwellers. What
question can be asked to highlight the problems
with this classification system?
A. Would all fish be classified into the same
subgroup, even though some live in lakes and
others in oceans?
B. Are penguins classified like other birds, even
though they don't fly?
C. Would two different breeds of dogs be classified
into the same subgroup?
D. How many animals can fit into each subgroup?

she forgot to record a transaction

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.