Need help on the second question I got it wrong

You want to cultivate some exotic plants at your farm. however, the climate is chillier than the temperature range favorable to the crop. which is the best method to use for the cultivation of this exotic crop? a. use a crop rotation method b. use a lot of fertilizer c. prepare the seed bed properly d. use a greenhouse e. use irrigation

In a population that is in hardy-weinberg equilibrium, there are two possible alleles for a certain gene, a and a. if the frequency of allele a is 0.4, what fraction of the population is heterozygous? a. 0.40 b. 0.60 c. 0.16 d. 0.48

Consider the following planned experiment. factor experimental group control group light exposure tots of sun tots of sun amount of water weekly weekly type of soil nutrient rich nutrient rich size of pot large which variable is being tested in this experiment? small a. size of pot b. type of soil c. light exposure d. amount of water