Q 1 . How many significant figures are in the following measurement? 0.0009(1 point) 1

5

4

3

Q 2. Three unique samples are weighed on different scales at separate laboratories across the country. The first has a weight of 31.2 lbs, the second sample weighs 38.02 lbs, while the third measures 45 lbs. How much is the total combined weight of all of these samples?(1 point)

114.22 lbs

110 lbs

114 lbs

114.2 lbs

Q 3. A track coach measures the 100-meter time of a track athlete. The runner completes the distance in 11.5 seconds. If the stopwatch has an uncertainty of 1.7%, what is the amount of uncertainty in the time?(1 point)
(1 point)

11.5 s ± 0.19 s
11.5 s plus or minus 0.19 s

11.5 s ± 0.20 s
11.5 s plus or minus 0.20 s

11.5 s ± 0.1955 s
11.5 s plus or minus 0.1955 s

11.5 s ± 0.196 s

Q 4. The speed of a bullet train is measured to be 312.0 mph ± 3.9 mph. What is the percent uncertainty in this measurement?(1 point)

1.3%

1.2%

1.25%

0.0125%

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

answer: the rock sample is a sedimentary rock.

explanation:

it is given that:

mass of rock sample, m = 2.7 g

volume of rock sample,

so, density of rock sample will be

since, the density of rock sample is . hence, the rock sample is a sedimentary rock, whose densities varies between .