Pla this is for my homwork. pla me! write it as a fraction and decimal. and explain! 82/4+20-15?

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

Negative 5 1/12 + negative 4 1/4 + 6 3/4

Select the number of ways in which a line and a circle can intersect