Answer
a) $1.9m$
b) $1.09*10^{14}s$
c) $2.2*10^{-4} m/s$
d) $5.7*10^{10} m^2$
Work Step by Step
First identify the type of non-standard unit the problem presents, then find the appropriate SI unit to convert to. After, round to the number of significant digits in the original unit of measurement.
a) convert inches to meters $75in \times \frac{1ft}{12in} \times \frac{0.3048m}{1ft} = 1.905m$
b) convert years to seconds $3.45yr \times \frac{365day}{1yr} \times \frac{24h}{1 day} \times \frac{60min}{1h} \times \frac{60s}{1min} = 1.087\times10^{14}s$
c) convert feet per day to meters per second $62ft/day \times \frac{.3048m}{1ft} \times \frac{1day}{24h} \times \frac{1h}{60min} \times \frac{1min}{60s} = 2.187\times10^{-4}$
d) convert miles squared to meters squared. Because this is a unit of area, each conversion must be done twice, once for each power. $2.2\times10^{4} mi^{2} \times (\frac{1.6093km}{1mi})^{2} \times (\frac{1000m}{1km})^{2} = 5.968\times10^{10}m^{2}$
