who wants to be my penpal on email for school because i need new friends and im 13 and only 10 through 15 can have it

Could someone me find the answer to this problem.

What is a carrier wave and how does it affect what you hear on the radio

At an oceanside nuclear power plant, seawater is used as part of the cooling system. this raises the temperature of the water that is discharged back into the ocean. the amount that the water temperature is raised has a uniform distribution over the interval from 10° to 25° c. what is the standard deviation of the temperature increase?