The half life of polonium is 139 days. you have a brand new sample of polonium that will not be useful to you after 80% of the material hasdistegraded. For how many days will you be able to use the polonium?

Jessica and martha each have a bag of cookies with unequal quantities. they have 30 cookies total between the two of them. each of them ate 6 cookies from their bag. the product of the number of cookies left in each bag is not more than 80. how many more cookies will jessica have martha? if x represents the number of cookies jessica started with, complete the statements below.the inequality that describes the relationship between the number of cookies each one of them has is x^2 - x +224 > = 0.jessica has at least cookies more than martha.

This is so hard and it’s for a test

If chord ab is congruent to chord cd, then what must be true about ef and eg?