Explanation:
8). 5 ft² into squared Inches:
=> since 1 ft² = 144 in²
=> 5x144
=> 720 in²
9). 16 000 cm² to m²:
=> since 1 m²= 10 000 cm²
=> 16 000 ÷ 10 000
=> 1.6 m²
10). 90 km/h to m/h
=> since 1000 m= 1 km
=> 90x1000
=> 90 000 m/h
11). 30 m/s to m/min
=> since 60 s= 1 min
=> 30÷60
=> 0.5 m/min
12). 15 rpm into rps
=> since 1 min= 60 s
=> 15x60
=> 900 rps