The Ebola virus disease (EVD) case fatality rate is around 30% among West African unvaccinated patients

The Ebola virus disease (EVD) case fatality rate is around 30% among West African unvaccinated patients.  In the problem below, assume that the probability of death due to EVD is exactly 30% (i.e., p=0.3), and that the fatality probability is constant across all individuals infected with the virus at any time.
(a)  Find the exact probability that 4 EVD patients will die in a clinic treating 6 unrelated EVD patients.
                                                                                                                           
(b)  Find the exact probability that 1 or more EVD patients will die in a clinic treating 6 unrelated EVD patients.