Zia used hypothetico-deductive reasoning.
The Hypothetico-Deductive method is a scientific model of reaserch. You make a hypothesis of what the problem is - keep in mind that, according to Einstein's thoughts, these hypothesis cannot be 100% verified, they can only be proven wrong - and once you have that, do deduce what the consequences might be.
The people represented by the ends of the bell-curve are the most rare.
This could mean that if it's an iq curve the people at the ends have either a really high or really low iq etc.
2 alleles which are both equally expressed is known as co-dominance, this occurs in the blood when someone has AB blood for example, the A and B alleles have co-dominance.
The right answer is common error.
A common error (or random error) is when, from one measure to another, the value obtained may be overvalued or underestimated in relation to the real value.
An example of a random error is the measurement of time with a timer. The error comes from the reaction time of the experimenter at start-up and at the end of the timer. Since this reaction time is not always the same, the measured value can be overestimated or underestimated. It is understandable that a repetition of the measures can alleviate the random error.
Photosynthetic - relating to or involved in the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.
Hope that this was helpful :)
