Remain constant. mass (on) = 4x10stg speed(s) = 5000m's time (t) = 2​

Electric charge is uniformly distributed inside a nonconducting sphere of radius 0.30 m. the electric field at a point p, which is 0.50 m from the center of the sphere, is 15,000 n/c and is directed radially outward. what is the maximum magnitude of the electric field due to this sphere

Can anybody me with this? ? (picture included.)

Achild has maximum walking speed of 1.6 m/s. what is the length of the child's legs? 0.26 m