A 9.0-V battery costs 1.49 and will run a portable CD player for ...

[Pea0909berry]

A 9.0-V battery costs 1.49 and will run a portable CD player for 6.0 hours before running down and needing to be replaced.
 
  If this battery supplies a current of 25 mA to the player, what is the cost of the energy provided by the battery in dollars per kWh?
  A) 11/kWh B) 11,000/kWh C) 1100/kWh D) 110/kWh

Question 2

A summary of the nuclear reactions that power our sun is 4p  4He + 2e-, with masses of 938.272 MeV/c2 for a proton, 3727.38 MeV/c2 for the helium nucleus, and 0.511 MeV/c2 for each electron.
 
  How much energy is released by each of these reactions? A) 24.69 MeV
  B) 28.3 MeV
  C) 2790.13 MeV
  D) 279.01 MeV

[rleezy04]

Answer to Question 1

C

Answer to Question 2

A

[Pea0909berry]

Thanks for the timely response, appreciate it

[bulacsom]

Wow, this really help