Suppose That Mercury Grew to Its Present Size in 1

Suppose that Mercury grew to its present size in 1 million years through the accretion of particles averaging 100 g each. On average how many particles did Mercury capture each second? Note: Mercury has a mass of 3.3 10 23 kg and a radius of 2439 km.

A) about 24 particles per second
B) about 3.3*10²¹particles per second
C) about 67 particles per second
D) about 100 million particles per second
E) about 100 billion particles per second