Answer: 
beta particles
Explanation:
Given mass = 14.0 g
Molar mass = 137 g/mol
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number 
of particles.
1 mole of cesium contains atoms =
0.102 moles of cesium contains atoms = 
The relation of atoms with time for radioactivbe decay is:
Where 
=atoms left undecayed
= initial atoms
t = time taken for decay = 3 minutes
= half life = 30.0 years = 
minutes
The fraction that decays : 
Amount of particles that decay is = 
Thus beta particles are emitted by a 14.0-g sample of cesium-137 in three minutes.
Answer:
Energy= 46.08KJ
Explanation:
Given that the power needed to light each bulb is 32W
We know that Power = 
The energy needed to light one bulb=
Given time = 1minute = 60 seconds
Energy = 
=1920J
Therefore energy needed to light one bulb is 1920J
The energy needed to light 24 bulbs = 
=46080J=46.08KJ
Speed is equal to distance traveled divided by the time. So it's 3.5 m/s
Answer:
Force, |F| = 2100 N
Explanation:
It is given that,
Water from a fire hose is directed horizontally against at a rate of 50.0 kg/s, 
Initial speed, v = 42 m/s
The momentum is reduced to zero, final speed, v = 0
The relation between the force and the momentum is given by :
|F| = 2100 N
So, the magnitude of the force exerted on the wall is 2100 N. Hence, this is the required solution.
