Answer:
Current, I = 2.3 A
Explanation:
We have,
Voltage of the battery in a circuit is 9 volts
Resistance of the circuit is 4 ohms
It is required to find the current in a circuit. When the voltage and the resistance of the circuit is given then we can find the current in it is given by Ohm's law as :

I is electric current

or
I = 2.3 A
So, the current in the circuit is 2.3 A.
Answer:
here as we increase the distance the intensity will decrease and hence the amplitude of the electric field will decrease and vice-versa
Explanation:
As wee know that the amplitude of the wave will decide the energy of the wave
Here we know that energy density of electromagnetic wave is given as

now we have

so here we can say that intensity of the wave at the given distance from the source is given by formula

so here as we increase the distance the intensity will decrease and hence the amplitude of the electric field will decrease and vice-versa.
Chan Hee can expect to observe about the samples after 16 days is that three-fourths of each sample will have undergone radioactive decay. The best answer is letter B.
Alright well the Answer to your question is A). Screw
Hope this helps have a nice day : )
If u want i can explain why
Similar elements with similar properties were in the same groups and periods for instance lithium(Li) and sodium(Na) are alkaline metals and so belong to the same group (that is group 1).Also Hydrogen(H) and Helium(He) both have only one shell or energy level and so belong to the same period.