Answer
a) $3.156\times 10^{7}s$
b) $3.156\times 10^{16}ns$
c) $3.169\times 10^{-8}$year
Work Step by Step
a) 1 year = $(1 year)(\frac{3.156\times 10^{7}s}{1 year})=3.156\times 10^{7}s$
b) 1 year = $(1 year)(\frac{3.156\times 10^{7}s}{1 year})(\frac{1\times 10^{9}ns}{1s})=3.156\times 10^{16}ns$
c) $1 s = (1 s)(\frac{1 year}{3.156\times 10^{7}s})=3.169\times 10^{-8}year$