12 analyze what mass of radioactive isotope
will be left after three half-lives?

1/8 of original sample.

Explanation:

Consider your final amount is 100 g.

After three half lives:

at 0 = 100 g

1 half life = 100/2  = 50 g

2 half life = 50/2 = 25 g

3 half life = 25/2 = 12.5 g

Know multiply the amount after three half lives with 8.

12.5 g × 8 = 100 g

So, after three half lives 1/8 of original sample is present.

starchy vegetables are high in carbohydrates.

starchy vegetables contain more carbohydrates than non-starchy vegetables.

explanation:

there are two primary categories of carbohydrates, essentially differentiated on the basis of their carbohydrate content (which is in the form of starch - a complex carbohydrate):

those vegetables which contain little amounts of starch are termed as non-starchy vegetables, and some examples include: artichokes, broccoli and bean sprouts.

vegetables high in their starch content are distinguished as starchy vegetables, and some examples include: potatoes, chickpeas and corn.

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