1-C. By doing so, you were using the number 10 as the unit for your calculation, a counting system referred to as the base-10 system.By doing so, you were using the number 10 as the unit for your calculation, a counting system referred to as the base-10 system.
2-C. For example, Britain once used a complicated counting system for its currency units; 1 pound equaled 20 shillings, but 1 shilling equaled 12 pennies.For example, Britain once used a complicated counting system for its currency units; 1 pound equaled 20 shillings, but 1 shilling equaled 12 pennies.
3-C. (1) GPS units interfering with radio reception.(1) GPS units interfering with radio reception.
(1)GPSユニットは、干渉します、無線受信とダヨ。
4-C. Also, in extreme situations such as when hikers get lost in the wilderness, GPS units can even save lives.Also, in extreme situations such as when hikers get lost in the wilderness, GPS units can even save lives.