Randomization in an experiment means that the experimental units or subjects are selected as a simple random sample from the whole population
under study.

Randomization allows a sample or small groups with similar characteristics to determine a probability or to hypothesize an event, that is why this type of samples is important in an experiment, that is, to carry it out in a random way.

Step-by-step explanation:

For example;

If a crop at a certain time of year, for example in summer, is affected by a certain fungus, to know if it is really the time of year that affects this problem, random samples of the same crop with the same characteristics and put it to the test at another time of the year to see if the weather is really a risk factor in the spread of this fungus.

add all the numbers and check the ones place.

the answer is 486. as the ones place is more than 4, the estimation will be the next 10 ie, 490

i think the answer is b.

step-by-step explanation:

not 100% sure though.