Ithink i know the answer but i am not sure

which shows how many centimeters are in 3.14203 × 10-4 to three significant figures?

a.
3.14 × 10-1 mm

b.
3.14203 × 10-1 mm

c.
3.10 × 10-1 mm

d.
3.142 × 10-1 mm

What is the primary force that suspension bridges use cables to hold their spans up? a. tension force b. resistance force c. normal force d. elastic force e. applied force

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?

On mars a rock falls an unknown vertical distance from a resting position and lands in a crater. if it takes the rock 2.5 seconds to fall, how high is the cliff the rock fell from? mars' surface gravity is 3.8 m/s2.