Density = Mass / Volume
Density of stone = 100 / 10 = 10 g/mL
If the density is higher than water, then the object will sink. If the density of the object is lower than water, then the object will float.
Since the density of the rock is 10g/mL and the density of the water is 1g/mL, the stone will sink.
(a) 
First of all, we need to calculate the acceleration of the person, by using the following SUVAT equation:

where
v = 0 is the final velocity
u = 20.0 m/s is the initial velocity
a is the acceleration
d = 1.00 cm = 0.01 m is the displacement of the person
Solving for a,

And the average force on the person is given by

with m = 75.0 kg being the mass of the person. Substituting,

where the negative sign means the force is opposite to the direction of motion of the person.
b) 
In this case,
v = 0 is the final velocity
u = 20.0 m/s is the initial velocity
a is the acceleration
d = 15.00 cm = 0.15 m is the displacement of the person with the air bag
So the acceleration is

So the average force on the person is

Answer :
The answer is clearly C
Explanation:
Because the only way currents move are to the side
Answer:
<u>Translated from Polish language:</u>
- Coil connected in series ul = 120 resistor ur = 100 and capacitor uc = 50 Voltage with voltmeter must not be:
- The voltmeter must not be connected in series rather it should be connected in parallel to the circuit to provide much effective results for analyzing the circuits potential difference.