Find the magnitude of the complex number `z = sqrt(15) + 2 i `. Give an exact answer.

`|z|` =  

Box 1: Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4)
Enter DNE for Does Not Exist, oo for Infinity
Decimal values are not allowed