Confused with half life /compound interest problems
1. fermium-252 decays in 10 minutes to 76.1% of its original
mass. find the half-life of fermium-252.
2. how long do you have to wait until 15mg of beryllium-7 have
decayed to 4mg, if the half-life of beryllium-7 is 53.12 days?

With these 5 geometry questions! pls 1.)quadrilateral abcd is inscribed in this circle. what is the measure of ∠a ? enter your answer in the box.°2.)quadrilateral abcd is inscribed in a circle. what is the measure of angle a? enter your answer in the box. m∠a= 3.)quadrilateral abcd is inscribed in this circle. what is the measure of angle b? enter your answer in the box. m∠b= °4.)quadrilateral abcd is inscribed in this circle. what is the measure of angle a? enter your answer in the box.°5.) quadrilateral abcd is inscribed in this circle. what is the measure of angle c? enter your answer in the box.°