Milkweed, tobacco, and poison ivy plants have adapted what type of measures to protect themselves?

These plants have adapted chemical measures to protect themselves.

Explanation:

Milkweed:

It has ability to protect itself. They produce sandpapery leaves (toxins) that can stop human heart. For insects they produce a poison which glue their mouth of insects.  

Tobacco:

Its leaves emit a chemical. When hornworm caterpillars eat these leaves then that chemical mixed with their spit and they doom into their own spit.  

Poison Ivy:

This plant has a skin irritant and use this irritant to protect itself from caterpillars and slugs.

Hence, these plants use chemicals for their defense.

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.

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