Write a number that has a zero in the tens place draw a quick picture for your number

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?

This race was first held in 1953 on august 16th. every decade the race finishes with a festival. how many years is this?

Which of the following answers is 5/25 simplified? 1/5 5/5 2/5 1/25