A laboratory is suspected to be contaminated with radiation from a radioactive material. Which of the following detection instruments can be best used to detect this radiation? 1) An X-ray film, because it can detect the low frequency X-rays.

2) An X-ray film, because it can detect the low energy infrared radiation.

3) A Geiger counter, because it can detect the high energy gamma rays.

4) A Geiger counter, because it can detect the highly penetrating ultraviolet radiation.

Answer asap need to be answered by wednesday morning explain how a buffer works, using an ethanoic acid / sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.