You have 2,112 grams of a radioactive kind of mercury. How much will be left after 188 days if it's half-life is 47 days?

This is different from the first one can someone me

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)

Asap will give brainiest to first person to answer what is the measure of angle b in the triangle? enter your answer in the box.m∠b=