A sample of phosphorus -32 has a mass of 20 grams. After 30 days, there are only 5 grams of the sample remains. What is the half-life of P-32?

i believe it is b. what was the cause of the big bang

hope this !

"i have always loved contemporary art and made it a general goal to work within the field. after a few nonprofit internships at museums and galleries, i decided to try the for-profit art world and was offered a job as the ad assistant at the magazine. i much prefer the pace of the for-profit art community and have stayed with the company for three years, with a promotion to an account manager last spring."

i just did this and got a 100.

the answer is b i think

i think the answer would be b