Which radioisotope is used as a tracer in nuclear scanning?

Gymnast always perform on padded mats. how does the mats protect the gymnast

Which of the following is true for a reliable scientific source? it cites logic. it cites opinions. it cites valid data. it cites common sense.

Growing crops in places where major pests don't live using beneficial insects to eat harmful insects using a rat trap instead of a rodenticide developing drought-resistant tomato plants using beneficial insects or natural oils to repel pests planting a different crop every year to fake out the pests keeping food covered to deter ants and rodents developing bean plants with a resistance to fungus picking caterpillars off tomato plants cultivation practice biological control cultural control genetic resistance natural chemicals