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:
gamma rays, ultraviolet, infrared, radio
Explanation:
Because on the Electromagnetic spectrum wavelength increases from the gamma end to radio end and frequency decrease in that order
Explanation:
Let us first calculate long does it take to go 12m at 30m/s( assumed speed)
12/30 = 0.4 seconds
horizontal distance the ball drop in that time
H= (0)(0.4)+1/2(-9.8)(0.4)2
H= -0.78m
negative sign shows that the height of the ball at the net from the top.
Height of the ball at the net and from the ground= H1-H=2.4-0.78=1.62m
As 1.62m>0.9m so the ball will clear the net.
H_1= V0y t’ + ½ g t’^2
-2.4= (0)t’ + ½ (-9.8) t’^2
t’= 0.69s
X’=V0x t’
X’=(30)(0.96)
X’= 20.7m