Answer:
Step-by-step explanation:
charge on the shell = 4πR² x charge density 
= 4 x 3.14 x 7.5² x 10⁻⁴ x 10⁻³ C 
= 706.5 x 10⁻⁷ C 
electric field = k Q / d² , d is distance of point from centre 
= 9 x 10⁹ x 706.5 x 10⁻⁷ / 10²
= 6358.5 N /C 
= 6.358 kV / m