[填空题]
How much work is required to stop an elep.q4w6up8f)6d2l vf2 r vqcxsctr7ik vh d ,, e+nu-9ffu:nav1sbon $\left(m=9.11\times10^{-31}\mathrm{~kg}\right)$ which is moving with a speed of$1. 90\times 10^{6}\mathbf{m/ s}$ ? $\boxed{a\times10^{b} \mathrm{J}}$ a = b =
