Placing shielding around a radioactive source helps protect from harm. A Geiger counter is used to determine how much radiation is still passing through the shielding. Determine from the information given the Geiger counter reading for a gamma source with 4 sheets of lead shielding.

How is the carbon cycle related to global warming ?

All organisms contribute some water to the water cycle by conducting

Can happen anywhere along the spine if the neural tube does not close all the way. the backbone that protects the spinal cord does not form and close as it should. this often results in damage to the spinal cord and nerves. a) cleft palate b) spina bifida c) encephalocele d) down's syndrome