I have a very hard question if I get it right it brings up my grades. Please help me it's timed.

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?

Which number line represents the solution set for the inequality -1/2x> 24?

What is the value for this expression? 2e-5