Answer:
That is administered and controlled
Step-by-step explanation:
A variable is the condition or a product that may vary without the influence of any investigator. Such variables can be found abundantly in our daily lives, ranging from air to sunlight. Controlling such variables ensures the limitation of their influence on the outcome of an experiment. In connection to this experiment, the variables that are controlled are the mineral content in the water, the amount of bacteria food, the amount of light and the the constant temperature of 20 degrees C.
If not administered or these variables controlled, the experiment would not clearly explain the impact of caffeine on the heart beat of the water fleas as other variables may have influenced it. Thus variables are controlled to study the singular impact of any agent or effect.
Answer:
Common Kingfishers measure 17 – 19 centimetres in length, weigh between 34 – 46 grams and have a wingspan of 25 centimetres. Their beak is around 4 centimetres long and pointed. Kingfishers have short, orange coloured legs. Kingfishers are very brightly coloured. The colour of their wings is a blue/green colour and their upperparts, rump and tail are a bright blue colour. Their underparts are bright orange and they have a small, white bib underneath their beaks, on their throats.
Explanation:
Answer:
number three is ghe real answer
Answer: neutral
Explanation: The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.