please solve part A and part B

A 6.0-mm-diameter proton beam carries a total current of 1.2 mA . The current density in the proton beam, which increases with distance from the center, is given by J = Jedge (r/ R) , where R is the radius of the beam and Jedge is the current density at the edge. Part A How many protons per second are delivered by this proton beam? Express your answer using two significant figures. AEQ ? N = protons per second Submit Request Answer Part B Determine the value of Jedge- Express your answer to two significant figures and include the appropriate units