Answer:
 B = 0.0087 T
Step-by-step explanation:
given, 
Length of solenoid (L)= 83 cm = 0.83 m 
radius of the solenoid (r)= 2.10 cm = 0.021 m
number of turns (N)= 1600 turns 
current (I)= 3.60 A 
Using magnetic field formula 
 
 
 

 B = 0.0087 T
the magnitude of magnetic field inside the solenoid is equal to B = 0.0087 T