Alyssa and Gabriel play the following game. Alyssa rolls a die. If she rolls a​ 1, 2, or​ 3, Gabriel gives Alyssa ​$. If Alyssa rolls a 4 or​ 5, Gabriel gives Alyssa ​$. ​However, if Alyssa rolls a​ 6, she gives Gabriel ​$.12 ​a) Determine​ Alyssa's expectation.
​b) Determine​ Gabriel's expectation.