Explanation:
Percentage w/v means that weight of solute present in 100 ml of a solution. Hence, 15% w/v means that 15 gram of solute per 100 ml of solution.
Hence, for 2 L (or 2000 mL) preparation the amount of mass will be calculated as follows.

= 300 g
Thus, we can conclude that weight of Tris-HCL required is 300 g.
There are 75% chances that their offsprings will be checkered.
Explanation:
The gene version allele is received by an individual and if they are different then the gene of the parent which is dominating is expressed in the offspring. However, in the case of co dominance the offspring gets the trait of both parent alleles.
So, in this case the mating of checkered rooster and checkered hen with co-dominance in their trait of genes will produce checkered offspring with a chance of 75 percent as can be calculated by the punnet square. The result will be 3 out of 4 checkered offspring.
As water is cooled from 4 to 0, its density "decreases." Density is the amount of substance per a specific volume. So, if the water cools it's density decreases, but as the temperature rises it's density will increase because liquid to a gas and a gas has a high density then a liquid.
Hope this helps.
It’s carbon dioxide + water > glucose + oxygen + water and energy produced in the form of ATP
The studies by Muzafer Sherif (utilizing a fixed spot of light) and Solomon Asch (utilizing different line lengths) illustrate that the group often has a significant effect on our individual judgment and behavioral conformity.
The studies were based on group influence on individuals.