[填空题]
A person scuffing her feet on a wool rubf h z:yw5p n uj,ls*.pqut5,7g on akeyv9fq5x9 l85gi ov , dry day accumulates a net charge ogq5ivkfxle 99, 8ov y5f $-42\,\mu C\,.$ How many excess electrons does she get, $ \times10^{14 }\,electrons$
by how much does her mass increase? $ \times10^{-16 }kg$
