An early code used in radio transmission involved using codewords that consist of binary

bits and contain the same number of $1$s$.$ Thus, the $2-$out$-$of$-5$ code only transmits blocks of $5$

bits in which $2$ bits are $1$ and the others $0.$

b$.$ Suppose that the code is used to transmit blocks of binary bits. How many

bits can be transmitted per codeword?