Fluorine-18 undergoes positron emission as shown: 18 F = 4x + til
Enter the appropriate values for A and Z and the chemical
symbol for X

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

Pastoral farming is best described as a. a method of raising livestock and moving herds b. an african method of agriculture c. a method of cultivating crops on poor soils d. a common method of desert farming select the best answer from the choices provided a b c d