What are some words to describe body parts of a monster like gigantic eyes etc?
blood thirsty eyes staring at you
There are many different ways of saying monster in Japanese, it just depends on what kind of monster it is: Obake means goblin Yajuu is beast, monster or wild animal Kaijuu, Monsuta, and kaibutsu are all just different words for monster. However, bakemono is the most common way and it's just a general way of saying monster.
Quanitive observation is the mathematical aspect of the experiment, such as the amount of water used or the height of a plant. Qualitive observation is using descriptions and words to describe parts of the experiment. One example is the chemical color change of a gas (what shade of color does it have?)