There are three types of vaccines $A_1$, $A_2$, $A_3$, available in the market to protect the population of the country from the spread of a certain infection. According to a survey conducted, it was found that $25\%$ of the population was given Vaccine $A_1$, $35\%$ of the population was given Vaccine $A_2$ and $40\%$ of the population was given Vaccine $A_3$. The survey also stated that the probabilities that Vaccines $A_1$, $A_2$ and $A_3$ would protect against the infection were $60\%$, $55\%$ and $50\%$ respectively. Based on the above information, answer the following questions: