PLZ help i got 2 hrs plz i beg of u

Bismuth-210 is an isotope that radioactively decays by about 13% each day, meaning 13% of the remaining bismuth-210 transforms into another atom (polonium-210 in this case) each day. if you begin with 233 mg of bismuth-210, how much remains after 8 days?

The center of the circumscribed circle lies on line segment and the longest side of the triangle is equal to the of the circle.

Hurry which expression is equivalent to 3√x^5y?