I think it's electromagnetic
Answer:19.5 J
Explanation:
Given
mass of block=3 kg
angular frequency=20 rad/sec
spring constant 
we know total energy remain conserved
Where 
=kinetic energy
=potential Energy
When mass reaches amplitude its velocity becomes zero
there is only potential energy which is equal to Total energy
<span>The weight of the rock is 138n when accelerating downward at 3.5m/ s2.Weight is a measurement of the force of gravity on an objects mass. Therefore as long as the force of gravity is the same and the mass of the rock is the same the weight should also be the same.</span>
If these were the missing choices:
a)
Consumers fill out questionnaires concerning
their need for new products.
b)
Consumers vote for politicians who decide which
kind of research to support
c)
Consumers decide what to buy and what not to buy
d)
Consumers influence the decisions of private
foundations by deciding where to donate money.
My answer would be: c) <span>Consumers decide what to buy and what not to buy</span>
Every growth is based on the demand of the people. If a good or service is needed then its demand will increase. If a good or service is not needed then its demand will decrease until such time that said good or service will be eliminated.
